Automatic date update in version.in

[binutils-gdb.git] / gdb / language.h

diff --git a/gdb/language.h b/gdb/language.h
index 57e48bd19b1f30fc1af873b6db449a836147335f..f2885000259b2df35dbd0f555a15323f88c22630 100644 (file)
--- a/gdb/language.h
+++ b/gdb/language.h
@@ -1,6 +1,6 @@
 /* Source-language-related definitions for GDB.
 
 /* Source-language-related definitions for GDB.
 

-   Copyright (C) 1991-2017 Free Software Foundation, Inc.
+   Copyright (C) 1991-2022 Free Software Foundation, Inc.

 
    Contributed by the Department of Computer Science at the State University
    of New York at Buffalo.
 
    Contributed by the Department of Computer Science at the State University
    of New York at Buffalo.


@@ -24,32 +24,24 @@
 #define LANGUAGE_H 1
 
 #include "symtab.h"
 #define LANGUAGE_H 1
 
 #include "symtab.h"

-#include "common/function-view.h"
+#include "gdbsupport/function-view.h"
+#include "expression.h"

 
 /* Forward decls for prototypes.  */
 struct value;
 struct objfile;
 struct frame_info;
 
 /* Forward decls for prototypes.  */
 struct value;
 struct objfile;
 struct frame_info;

-struct expression;

 struct ui_file;
 struct value_print_options;
 struct type_print_options;
 struct lang_varobj_ops;
 struct parser_state;
 struct ui_file;
 struct value_print_options;
 struct type_print_options;
 struct lang_varobj_ops;
 struct parser_state;

-struct compile_instance;
+class compile_instance;
+struct completion_match_for_lcd;
+class innermost_block_tracker;

 
 #define MAX_FORTRAN_DIMS  7    /* Maximum number of F77 array dims.  */
 
 
 #define MAX_FORTRAN_DIMS  7    /* Maximum number of F77 array dims.  */
 

-/* range_mode ==
-   range_mode_auto:   range_check set automatically to default of language.
-   range_mode_manual: range_check set manually by user.  */
-
-extern enum range_mode
-  {
-    range_mode_auto, range_mode_manual
-  }
-range_mode;
-

 /* range_check ==
    range_check_on:    Ranges are checked in GDB expressions, producing errors.
    range_check_warn:  Ranges are checked, producing warnings.
 /* range_check ==
    range_check_on:    Ranges are checked in GDB expressions, producing errors.
    range_check_warn:  Ranges are checked, producing warnings.


@@ -61,16 +53,6 @@ extern enum range_check
   }
 range_check;
 
   }
 range_check;
 

-/* case_mode ==
-   case_mode_auto:   case_sensitivity set upon selection of scope.
-   case_mode_manual: case_sensitivity set only by user.  */
-
-extern enum case_mode
-  {
-    case_mode_auto, case_mode_manual
-  }
-case_mode;
-

 /* array_ordering ==
    array_row_major:     Arrays are in row major order.
    array_column_major:  Arrays are in column major order.  */
 /* array_ordering ==
    array_row_major:     Arrays are in row major order.
    array_column_major:  Arrays are in column major order.  */


@@ -107,332 +89,565 @@ enum macro_expansion
 
 struct language_arch_info
 {
 
 struct language_arch_info
 {

-  /* Its primitive types.  This is a vector ended by a NULL pointer.
-     These types can be specified by name in parsing types in
-     expressions, regardless of whether the program being debugged
-     actually defines such a type.  */
-  struct type **primitive_type_vector;
+  /* A default constructor.  */
+  language_arch_info () = default;
+
+  DISABLE_COPY_AND_ASSIGN (language_arch_info);
+
+  /* Set the default boolean type to be TYPE.  If NAME is not nullptr then
+     before using TYPE a symbol called NAME will be looked up, and the type
+     of this symbol will be used instead.  Should only be called once when
+     performing setup for a particular language in combination with a
+     particular gdbarch.  */
+  void set_bool_type (struct type *type, const char *name = nullptr)
+  {
+    gdb_assert (m_bool_type_default == nullptr);
+    gdb_assert (m_bool_type_name == nullptr);
+    gdb_assert (type != nullptr);
+    m_bool_type_default = type;
+    m_bool_type_name = name;
+  }
+
+  /* Set the type to be used for characters within a string.  Should only
+     be called once when performing setup for a particular language in
+     combination with a particular gdbarch.  */
+  void set_string_char_type (struct type *type)
+  {
+    gdb_assert (m_string_char_type == nullptr);
+    gdb_assert (type != nullptr);
+    m_string_char_type = type;
+  }
+
+  /* Return the type for characters within a string.  */
+  struct type *string_char_type () const
+  { return m_string_char_type; }
+
+  /* Return the type to be used for booleans.  */
+  struct type *bool_type () const;
+
+  /* Add TYPE to the list of primitive types for this particular language,
+     with this OS/ABI combination.  */
+  void add_primitive_type (struct type *type)
+  {
+    gdb_assert (type != nullptr);
+    primitive_types_and_symbols.push_back (type_and_symbol (type));
+  }

 
 

-  /* Symbol wrappers around primitive_type_vector, so that the symbol lookup
-     machinery can return them.  */
-  struct symbol **primitive_type_symbols;
+  /* Lookup a primitive type called NAME.  Will return nullptr if no
+     matching type is found.  */
+  struct type *lookup_primitive_type (const char *name);
+
+  /* Lookup a primitive type for which FILTER returns true.  Will return
+     nullptr if no matching type is found.  */
+  struct type *lookup_primitive_type
+    (gdb::function_view<bool (struct type *)> filter);
+
+  /* Lookup a primitive type called NAME and return the type as a symbol.
+     LANG is the language for which type is being looked up.  */
+  struct symbol *lookup_primitive_type_as_symbol (const char *name,
+                                                 enum language lang);
+private:
+
+  /* A structure storing a type and a corresponding symbol.  The type is
+     defined at construction time, while the symbol is lazily created only
+     when asked for, but is then cached for future use.  */
+  struct type_and_symbol
+  {
+    /* Constructor.  */
+    explicit type_and_symbol (struct type *type)
+      : m_type (type)
+    { /* Nothing.  */ }
+
+    /* Default move constructor.  */
+    type_and_symbol (type_and_symbol&&) = default;
+
+    DISABLE_COPY_AND_ASSIGN (type_and_symbol);
+
+    /* Return the type from this object.  */
+    struct type *type () const
+    { return m_type; }
+
+    /* Create and return a symbol wrapping M_TYPE from this object.  */
+    struct symbol *symbol (enum language lang)
+    {
+      if (m_symbol == nullptr)
+       m_symbol = alloc_type_symbol (lang, m_type);
+      return m_symbol;
+    }
+
+  private:
+    /* The type primitive type.  */
+    struct type *m_type = nullptr;
+
+    /* A symbol wrapping M_TYPE, only created when first asked for.  */
+    struct symbol *m_symbol = nullptr;
+
+    /* Helper function for type lookup as a symbol.  Create the symbol
+       corresponding to type TYPE in language LANG.  */
+    static struct symbol *alloc_type_symbol (enum language lang,
+                                            struct type *type);
+  };
+
+  /* Lookup a type_and_symbol entry from the primitive_types_and_symbols
+     vector for a type matching NAME.  Return a pointer to the
+     type_and_symbol object from the vector.  This will return nullptr if
+     there is no type matching NAME found.  */
+  type_and_symbol *lookup_primitive_type_and_symbol (const char *name);
+
+  /* Vector of the primitive types added through add_primitive_type.  These
+     types can be specified by name in parsing types in expressions,
+     regardless of whether the program being debugged actually defines such
+     a type.
+
+     Within the vector each type is paired with a lazily created symbol,
+     which can be fetched by the symbol lookup machinery, should they be
+     needed.  */
+  std::vector<type_and_symbol> primitive_types_and_symbols;

 
   /* Type of elements of strings.  */
 
   /* Type of elements of strings.  */

-  struct type *string_char_type;
+  struct type *m_string_char_type = nullptr;

 
   /* Symbol name of type to use as boolean type, if defined.  */
 
   /* Symbol name of type to use as boolean type, if defined.  */

-  const char *bool_type_symbol;
+  const char *m_bool_type_name = nullptr;
+

   /* Otherwise, this is the default boolean builtin type.  */
   /* Otherwise, this is the default boolean builtin type.  */

-  struct type *bool_type_default;
+  struct type *m_bool_type_default = nullptr;

 };
 
 };
 

-/* A pointer to a function expected to return nonzero if
-   SYMBOL_SEARCH_NAME matches the given LOOKUP_NAME.
+/* In a language (particularly C++) a function argument of an aggregate
+   type (i.e.  class/struct/union) may be implicitly passed by reference
+   even though it is declared a call-by-value argument in the source.
+   The struct below puts together necessary information for GDB to be
+   able to detect and carry out pass-by-reference semantics for a
+   particular type.  This type is referred as T in the inlined comments
+   below.

 
 

-   SYMBOL_SEARCH_NAME should be a symbol's "search" name.
-   LOOKUP_NAME should be the name of an entity after it has been
-   transformed for lookup.  */
+   The default values of the fields are chosen to give correct semantics
+   for primitive types and for simple aggregate types, such as

 
 

-typedef int (*symbol_name_cmp_ftype) (const char *symbol_search_name,
-                                     const char *lookup_name);
+   class T {
+     int x;
+   };  */

 
 

-/* Structure tying together assorted information about a language.  */
+struct language_pass_by_ref_info
+{
+  /* True if an argument of type T can be passed to a function by value
+     (i.e.  not through an implicit reference).  False, otherwise.  */
+  bool trivially_copyable = true;
+
+  /* True if a copy of a value of type T can be initialized by
+     memcpy'ing the value bit-by-bit.  False, otherwise.
+     E.g.  If T has a user-defined copy ctor, this should be false.  */
+  bool trivially_copy_constructible = true;
+
+  /* True if a value of type T can be destructed simply by reclaiming
+     the memory area occupied by the value.  False, otherwise.
+     E.g.  If T has a user-defined destructor, this should be false.  */
+  bool trivially_destructible = true;
+
+  /* True if it is allowed to create a copy of a value of type T.
+     False, otherwise.
+     E.g.  If T has a deleted copy ctor, this should be false.  */
+  bool copy_constructible = true;
+
+  /* True if a value of type T can be destructed.  False, otherwise.
+     E.g.  If T has a deleted destructor, this should be false.  */
+  bool destructible = true;
+};
+
+/* Splitting strings into words.  */
+extern const char *default_word_break_characters (void);
+
+/* Base class from which all other language classes derive.  */

 
 struct language_defn
 
 struct language_defn

+{
+  language_defn (enum language lang)
+    : la_language (lang)
+  {
+    /* We should only ever create one instance of each language.  */
+    gdb_assert (languages[lang] == nullptr);
+    languages[lang] = this;
+  }
+
+  /* Which language this is.  */
+
+  const enum language la_language;
+
+  /* Name of the language.  */
+
+  virtual const char *name () const = 0;
+
+  /* Natural or official name of the language.  */
+
+  virtual const char *natural_name () const = 0;
+
+  /* Return a vector of file extensions for this language.  The extension
+     must include the ".", like ".c".  If this language doesn't need to
+     provide any filename extensions, this may be an empty vector (which is
+     the default).  */
+
+  virtual const std::vector<const char *> &filename_extensions () const
+  {
+    static const std::vector<const char *> no_extensions;
+    return no_extensions;
+  }
+
+  /* Print the index of an element of an array.  This default
+     implementation prints using C99 syntax.  */
+
+  virtual void print_array_index (struct type *index_type,
+                                 LONGEST index_value,
+                                 struct ui_file *stream,
+                                 const value_print_options *options) const;
+
+  /* Given a symbol VAR, the corresponding block VAR_BLOCK (if any) and a
+     stack frame id FRAME, read the value of the variable and return (pointer
+     to a) struct value containing the value.
+
+     VAR_BLOCK is needed if there's a possibility for VAR to be outside
+     FRAME.  This is what happens if FRAME correspond to a nested function
+     and VAR is defined in the outer function.  If callers know that VAR is
+     located in FRAME or is global/static, NULL can be passed as VAR_BLOCK.
+
+     Throw an error if the variable cannot be found.  */
+
+  virtual struct value *read_var_value (struct symbol *var,
+                                       const struct block *var_block,
+                                       struct frame_info *frame) const;
+
+  /* Return information about whether TYPE should be passed
+     (and returned) by reference at the language level.  The default
+     implementation returns a LANGUAGE_PASS_BY_REF_INFO initialised in its
+     default state.  */
+
+  virtual struct language_pass_by_ref_info pass_by_reference_info
+       (struct type *type) const
+  {
+    return {};
+  }
+
+  /* Return true if SYMBOL represents an entity that is not
+     supposed to be seen by the user.  To be used to filter symbols
+     during printing.  */
+  virtual bool symbol_printing_suppressed (struct symbol *symbol) const
+  {
+    return false;
+  }
+
+  /* The per-architecture (OS/ABI) language information.  */
+
+  virtual void language_arch_info (struct gdbarch *,
+                                  struct language_arch_info *) const = 0;
+
+  /* Find the definition of the type with the given name.  */
+
+  virtual struct type *lookup_transparent_type (const char *name) const
+  {
+    return basic_lookup_transparent_type (name);
+  }
+
+  /* Find all symbols in the current program space matching NAME in
+     DOMAIN, according to this language's rules.
+
+     The search is done in BLOCK only.
+     The caller is responsible for iterating up through superblocks
+     if desired.
+
+     For each one, call CALLBACK with the symbol.  If CALLBACK
+     returns false, the iteration ends at that point.
+
+     This field may not be NULL.  If the language does not need any
+     special processing here, 'iterate_over_symbols' should be
+     used as the definition.  */
+  virtual bool iterate_over_symbols
+       (const struct block *block, const lookup_name_info &name,
+        domain_enum domain,
+        gdb::function_view<symbol_found_callback_ftype> callback) const
+  {
+    return ::iterate_over_symbols (block, name, domain, callback);
+  }
+
+  /* Return a pointer to the function that should be used to match a
+     symbol name against LOOKUP_NAME, according to this language's
+     rules.  The matching algorithm depends on LOOKUP_NAME.  For
+     example, on Ada, the matching algorithm depends on the symbol
+     name (wild/full/verbatim matching), and on whether we're doing
+     a normal lookup or a completion match lookup.
+
+     As Ada wants to capture symbol matching for all languages in some
+     cases, then this method is a non-overridable interface.  Languages
+     should override GET_SYMBOL_NAME_MATCHER_INNER if they need to.  */
+
+  symbol_name_matcher_ftype *get_symbol_name_matcher
+       (const lookup_name_info &lookup_name) const;
+
+  /* If this language allows compilation from the gdb command line,
+     then this method will return an instance of struct gcc_context
+     appropriate to the language.  If compilation for this language is
+     generally supported, but something goes wrong then an exception
+     is thrown.  If compilation is not supported for this language
+     then this method returns NULL.  */
+
+  virtual std::unique_ptr<compile_instance> get_compile_instance () const;
+
+  /* This method must be overridden if 'get_compile_instance' is
+     overridden.
+
+     This takes the user-supplied text and returns a new bit of code
+     to compile.
+
+     INST is the compiler instance being used.
+     INPUT is the user's input text.
+     GDBARCH is the architecture to use.
+     EXPR_BLOCK is the block in which the expression is being
+     parsed.
+     EXPR_PC is the PC at which the expression is being parsed.  */
+
+  virtual std::string compute_program (compile_instance *inst,
+                                      const char *input,
+                                      struct gdbarch *gdbarch,
+                                      const struct block *expr_block,
+                                      CORE_ADDR expr_pc) const

   {
   {

-    /* Name of the language.  */
+    gdb_assert_not_reached ("language_defn::compute_program");
+  }
+
+  /* Hash the given symbol search name.  */
+  virtual unsigned int search_name_hash (const char *name) const;
+
+  /* Demangle a symbol according to this language's rules.  Unlike
+     la_demangle, this does not take any options.

 
 

-    const char *la_name;
+     *DEMANGLED will be set by this function.

 
 

-    /* Natural or official name of the language.  */
+     If this function returns false, then *DEMANGLED must always be set
+     to NULL.

 
 

-    const char *la_natural_name;
+     If this function returns true, the implementation may set this to
+     a xmalloc'd string holding the demangled form.  However, it is
+     not required to.  The string, if any, is owned by the caller.

 
 

-    /* its symtab language-enum (defs.h).  */
+     The resulting string should be of the form that will be
+     installed into a symbol.  */
+  virtual bool sniff_from_mangled_name
+       (const char *mangled, gdb::unique_xmalloc_ptr<char> *demangled) const
+  {
+    *demangled = nullptr;
+    return false;
+  }
+
+  /* Return demangled language symbol version of MANGLED, or NULL.  */
+  virtual gdb::unique_xmalloc_ptr<char> demangle_symbol (const char *mangled,
+                                                        int options) const
+  {
+    return nullptr;
+  }

 
 

-    enum language la_language;
+  /* Print TYPE to STREAM using syntax appropriate for this language.
+     LEVEL is the depth to indent lines by.  VARSTRING, if not NULL or the
+     empty string, is the name of a variable and TYPE should be printed in
+     the form of a declaration of a variable named VARSTRING.  */

 
 

-    /* Default range checking.  */
+  virtual void print_type (struct type *type, const char *varstring,
+                          struct ui_file *stream, int show, int level,
+                          const struct type_print_options *flags) const = 0;

 
 

-    enum range_check la_range_check;
+  /* PC is possibly an unknown languages trampoline.
+     If that PC falls in a trampoline belonging to this language, return
+     the address of the first pc in the real function, or 0 if it isn't a
+     language tramp for this language.  */
+  virtual CORE_ADDR skip_trampoline (struct frame_info *fi, CORE_ADDR pc) const
+  {
+    return (CORE_ADDR) 0;
+  }
+
+  /* Return class name of a mangled method name or NULL.  */
+  virtual char *class_name_from_physname (const char *physname) const
+  {
+    return nullptr;
+  }

 
 

-    /* Default case sensitivity.  */
-    enum case_sensitivity la_case_sensitivity;
+  /* The list of characters forming word boundaries.  */
+  virtual const char *word_break_characters (void) const
+  {
+    return default_word_break_characters ();
+  }

 
 

-    /* Multi-dimensional array ordering.  */
-    enum array_ordering la_array_ordering;
+  /* Add to the completion tracker all symbols which are possible
+     completions for TEXT.  WORD is the entire command on which the
+     completion is being made.  If CODE is TYPE_CODE_UNDEF, then all
+     symbols should be examined; otherwise, only STRUCT_DOMAIN symbols
+     whose type has a code of CODE should be matched.  */
+
+  virtual void collect_symbol_completion_matches
+       (completion_tracker &tracker,
+        complete_symbol_mode mode,
+        symbol_name_match_type name_match_type,
+        const char *text,
+        const char *word,
+        enum type_code code) const
+  {
+    return default_collect_symbol_completion_matches_break_on
+      (tracker, mode, name_match_type, text, word, "", code);
+  }

 
 

-    /* Style of macro expansion, if any, supported by this language.  */
-    enum macro_expansion la_macro_expansion;
+  /* This is a function that lookup_symbol will call when it gets to
+     the part of symbol lookup where C looks up static and global
+     variables.  This default implements the basic C lookup rules.  */

 
 

-    /* A NULL-terminated array of file extensions for this language.
-       The extension must include the ".", like ".c".  If this
-       language doesn't need to provide any filename extensions, this
-       may be NULL.  */
+  virtual struct block_symbol lookup_symbol_nonlocal
+       (const char *name,
+        const struct block *block,
+        const domain_enum domain) const;

 
 

-    const char *const *la_filename_extensions;
+  /* Return an expression that can be used for a location
+     watchpoint.  TYPE is a pointer type that points to the memory
+     to watch, and ADDR is the address of the watched memory.  */
+  virtual gdb::unique_xmalloc_ptr<char> watch_location_expression
+       (struct type *type, CORE_ADDR addr) const;

 
 

-    /* Definitions related to expression printing, prefixifying, and
-       dumping.  */
+  /* List of all known languages.  */
+  static const struct language_defn *languages[nr_languages];

 
 

-    const struct exp_descriptor *la_exp_desc;
+  /* Print a top-level value using syntax appropriate for this language.  */
+  virtual void value_print (struct value *val, struct ui_file *stream,
+                           const struct value_print_options *options) const;

 
 

-    /* Parser function.  */
+  /* Print a value using syntax appropriate for this language.  RECURSE is
+     the recursion depth.  It is zero-based.  */
+  virtual void value_print_inner
+       (struct value *val, struct ui_file *stream, int recurse,
+        const struct value_print_options *options) const;

 
 

-    int (*la_parser) (struct parser_state *);
+  /* Parser function.  */

 
 

-    /* Parser error function.  */
+  virtual int parser (struct parser_state *ps) const;

 
 

-    void (*la_error) (const char *);
+  /* Print the character CH (of type CHTYPE) on STREAM as part of the
+     contents of a literal string whose delimiter is QUOTER.  */

 
 

-    /* Given an expression *EXPP created by prefixifying the result of
-       la_parser, perform any remaining processing necessary to complete
-       its translation.  *EXPP may change; la_post_parser is responsible 
-       for releasing its previous contents, if necessary.  If 
-       VOID_CONTEXT_P, then no value is expected from the expression.  */
+  virtual void emitchar (int ch, struct type *chtype,
+                        struct ui_file *stream, int quoter) const;

 
 

-    void (*la_post_parser) (struct expression ** expp, int void_context_p);
+  virtual void printchar (int ch, struct type *chtype,
+                         struct ui_file * stream) const;

 
 

-    void (*la_printchar) (int ch, struct type *chtype,
-                         struct ui_file * stream);
+/* Print the character string STRING, printing at most LENGTH characters.
+   Printing stops early if the number hits print_max; repeat counts
+   are printed as appropriate.  Print ellipses at the end if we
+   had to stop before printing LENGTH characters, or if FORCE_ELLIPSES.  */

 
 

-    void (*la_printstr) (struct ui_file * stream, struct type *elttype,
+  virtual void printstr (struct ui_file *stream, struct type *elttype,

                         const gdb_byte *string, unsigned int length,
                         const char *encoding, int force_ellipses,
                         const gdb_byte *string, unsigned int length,
                         const char *encoding, int force_ellipses,

-                        const struct value_print_options *);
+                        const struct value_print_options *options) const;

 
 

-    void (*la_emitchar) (int ch, struct type *chtype,
-                        struct ui_file * stream, int quoter);

 
 

-    /* Print a type using syntax appropriate for this language.  */
+  /* Print a typedef using syntax appropriate for this language.
+     TYPE is the underlying type.  NEW_SYMBOL is the symbol naming
+     the type.  STREAM is the output stream on which to print.  */

 
 

-    void (*la_print_type) (struct type *, const char *, struct ui_file *, int,
-                          int, const struct type_print_options *);
+  virtual void print_typedef (struct type *type, struct symbol *new_symbol,
+                             struct ui_file *stream) const;

 
 

-    /* Print a typedef using syntax appropriate for this language.
-       TYPE is the underlying type.  NEW_SYMBOL is the symbol naming
-       the type.  STREAM is the output stream on which to print.  */
+  /* Return true if TYPE is a string type.  */
+  virtual bool is_string_type_p (struct type *type) const;

 
 

-    void (*la_print_typedef) (struct type *type, struct symbol *new_symbol,
-                             struct ui_file *stream);
+  /* Return a string that is used by the 'set print max-depth' setting.
+     When GDB replaces a struct or union (during value printing) that is
+     "too deep" this string is displayed instead.  The default value here
+     suits most languages.  If overriding then the string here should
+     ideally be similar in style to the default; an opener, three '.', and
+     a closer.  */

 
 

-    /* Print a value using syntax appropriate for this language.
-       
-       TYPE is the type of the sub-object to be printed.
+  virtual const char *struct_too_deep_ellipsis () const
+  { return "{...}"; }

 
 

-       EMBEDDED_OFFSET is the offset into the outermost object of the
-       sub-object represented by TYPE.  This is the object which this
-       call should print.  Note that the enclosing type is not
-       available.
+  /* If this returns non-NULL then the string returned specifies the name
+     of the implicit local variable that refers to the current object
+     instance.  Return NULL (the default) for languages that have no name
+     for the current object instance.  */

 
 

-       ADDRESS is the address in the inferior of the enclosing object.
+  virtual const char *name_of_this () const
+  { return nullptr; }

 
 

-       STREAM is the stream on which the value is to be printed.
+  /* Return false if the language has first-class arrays.  Return true if
+     there are no array values, and array objects decay to pointers, as in
+     C.  The default is true as currently most supported languages behave
+     in this manner.  */

 
 

-       RECURSE is the recursion depth.  It is zero-based.
+  virtual bool c_style_arrays_p () const
+  { return true; }

 
 

-       OPTIONS are the formatting options to be used when
-       printing.  */
+  /* Return the index to use for extracting the first element of a string,
+     or as the lower bound when creating a new string.  The default of
+     choosing 0 or 1 based on C_STYLE_ARRAYS_P works for all currently
+     supported languages except Modula-2.  */

 
 

-    void (*la_val_print) (struct type *type,
-                         int embedded_offset, CORE_ADDR address,
-                         struct ui_file *stream, int recurse,
-                         struct value *val,
-                         const struct value_print_options *options);
+  virtual char string_lower_bound () const
+  { return c_style_arrays_p () ? 0 : 1; }

 
 

-    /* Print a top-level value using syntax appropriate for this language.  */
+  /* Returns true if the symbols names should be stored in GDB's data
+     structures for minimal/partial/full symbols using their linkage (aka
+     mangled) form; false if the symbol names should be demangled first.

 
 

-    void (*la_value_print) (struct value *, struct ui_file *,
-                           const struct value_print_options *);
+     Most languages implement symbol lookup by comparing the demangled
+     names, in which case it is advantageous to store that information
+     already demangled, and so would return false, which is the default.

 
 

-    /* Given a symbol VAR, the corresponding block VAR_BLOCK (if any) and a
-       stack frame id FRAME, read the value of the variable and return (pointer
-       to a) struct value containing the value.
+     On the other hand, some languages have opted for doing symbol lookups
+     by comparing mangled names instead, for reasons usually specific to
+     the language.  Those languages should override this function and
+     return true.

 
 

-       VAR_BLOCK is needed if there's a possibility for VAR to be outside
-       FRAME.  This is what happens if FRAME correspond to a nested function
-       and VAR is defined in the outer function.  If callers know that VAR is
-       located in FRAME or is global/static, NULL can be passed as VAR_BLOCK.
+     And finally, other languages such as C or Asm do not have the concept
+     of mangled vs demangled name, so those languages should also override
+     this function and return true, to prevent any accidental demangling
+     through an unrelated language's demangler.  */

 
 

-       Throw an error if the variable cannot be found.  */
+  virtual bool store_sym_names_in_linkage_form_p () const
+  { return false; }

 
 

-    struct value *(*la_read_var_value) (struct symbol *var,
-                                       const struct block *var_block,
-                                       struct frame_info *frame);
-
-    /* PC is possibly an unknown languages trampoline.
-       If that PC falls in a trampoline belonging to this language,
-       return the address of the first pc in the real function, or 0
-       if it isn't a language tramp for this language.  */
-    CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR);
-
-    /* Now come some hooks for lookup_symbol.  */
-
-    /* If this is non-NULL, specifies the name that of the implicit
-       local variable that refers to the current object instance.  */
-
-    const char *la_name_of_this;
-
-    /* This is a function that lookup_symbol will call when it gets to
-       the part of symbol lookup where C looks up static and global
-       variables.  */
-
-    struct block_symbol (*la_lookup_symbol_nonlocal)
-      (const struct language_defn *,
-       const char *,
-       const struct block *,
-       const domain_enum);
-
-    /* Find the definition of the type with the given name.  */
-    struct type *(*la_lookup_transparent_type) (const char *);
-
-    /* Return demangled language symbol, or NULL.  */
-    char *(*la_demangle) (const char *mangled, int options);
-
-    /* Demangle a symbol according to this language's rules.  Unlike
-       la_demangle, this does not take any options.
-
-       *DEMANGLED will be set by this function.
-       
-       If this function returns 0, then *DEMANGLED must always be set
-       to NULL.
-
-       If this function returns 1, the implementation may set this to
-       a xmalloc'd string holding the demangled form.  However, it is
-       not required to.  The string, if any, is owned by the caller.
-
-       The resulting string should be of the form that will be
-       installed into a symbol.  */
-    int (*la_sniff_from_mangled_name) (const char *mangled, char **demangled);
-
-    /* Return class name of a mangled method name or NULL.  */
-    char *(*la_class_name_from_physname) (const char *physname);
-
-    /* Table for printing expressions.  */
-
-    const struct op_print *la_op_print_tab;
-
-    /* Zero if the language has first-class arrays.  True if there are no
-       array values, and array objects decay to pointers, as in C.  */
-
-    char c_style_arrays;
-
-    /* Index to use for extracting the first element of a string.  */
-    char string_lower_bound;
-
-    /* The list of characters forming word boundaries.  */
-    const char *(*la_word_break_characters) (void);
-
-    /* Add to the completion tracker all symbols which are possible
-       completions for TEXT.  WORD is the entire command on which the
-       completion is being made.  If CODE is TYPE_CODE_UNDEF, then all
-       symbols should be examined; otherwise, only STRUCT_DOMAIN
-       symbols whose type has a code of CODE should be matched.  */
-    void (*la_collect_symbol_completion_matches)
-      (completion_tracker &tracker,
-       complete_symbol_mode mode,
-       const char *text,
-       const char *word,
-       enum type_code code);
-
-    /* The per-architecture (OS/ABI) language information.  */
-    void (*la_language_arch_info) (struct gdbarch *,
-                                  struct language_arch_info *);
-
-    /* Print the index of an element of an array.  */
-    void (*la_print_array_index) (struct value *index_value,
-                                  struct ui_file *stream,
-                                  const struct value_print_options *options);
-
-    /* Return non-zero if TYPE should be passed (and returned) by
-       reference at the language level.  */
-    int (*la_pass_by_reference) (struct type *type);
-
-    /* Obtain a string from the inferior, storing it in a newly allocated
-       buffer in BUFFER, which should be freed by the caller.  If the
-       in- and out-parameter *LENGTH is specified at -1, the string is
-       read until a null character of the appropriate width is found -
-       otherwise the string is read to the length of characters specified.
-       On completion, *LENGTH will hold the size of the string in characters.
-       If a *LENGTH of -1 was specified it will count only actual
-       characters, excluding any eventual terminating null character.
-       Otherwise *LENGTH will include all characters - including any nulls.
-       CHARSET will hold the encoding used in the string.  */
-    void (*la_get_string) (struct value *value, gdb_byte **buffer, int *length,
-                          struct type **chartype, const char **charset);
-
-    /* Return an expression that can be used for a location
-       watchpoint.  TYPE is a pointer type that points to the memory
-       to watch, and ADDR is the address of the watched memory.  */
-    gdb::unique_xmalloc_ptr<char> (*la_watch_location_expression)
-         (struct type *type, CORE_ADDR addr);
-
-    /* Return a pointer to the function that should be used to match
-       a symbol name against LOOKUP_NAME. This is mostly for languages
-       such as Ada where the matching algorithm depends on LOOKUP_NAME.
-
-       This field may be NULL, in which case strcmp_iw will be used
-       to perform the matching.  */
-    symbol_name_cmp_ftype (*la_get_symbol_name_cmp) (const char *lookup_name);
-
-    /* Find all symbols in the current program space matching NAME in
-       DOMAIN, according to this language's rules.
-
-       The search is done in BLOCK only.
-       The caller is responsible for iterating up through superblocks
-       if desired.
-
-       For each one, call CALLBACK with the symbol.  If CALLBACK
-       returns false, the iteration ends at that point.
-
-       This field may not be NULL.  If the language does not need any
-       special processing here, 'iterate_over_symbols' should be
-       used as the definition.  */
-    void (*la_iterate_over_symbols)
-      (const struct block *block, const char *name, domain_enum domain,
-       gdb::function_view<symbol_found_callback_ftype> callback);
-
-    /* Various operations on varobj.  */
-    const struct lang_varobj_ops *la_varobj_ops;
-
-    /* If this language allows compilation from the gdb command line,
-       this method should be non-NULL.  When called it should return
-       an instance of struct gcc_context appropriate to the language.
-       When defined this method must never return NULL; instead it
-       should throw an exception on failure.  The returned compiler
-       instance is owned by its caller and must be deallocated by
-       calling its 'destroy' method.  */
-
-    struct compile_instance *(*la_get_compile_instance) (void);
-
-    /* This method must be defined if 'la_get_gcc_context' is defined.
-       If 'la_get_gcc_context' is not defined, then this method is
-       ignored.
-
-       This takes the user-supplied text and returns a new bit of code
-       to compile.
-
-       INST is the compiler instance being used.
-       INPUT is the user's input text.
-       GDBARCH is the architecture to use.
-       EXPR_BLOCK is the block in which the expression is being
-       parsed.
-       EXPR_PC is the PC at which the expression is being parsed.  */
-
-    std::string (*la_compute_program) (struct compile_instance *inst,
-                                      const char *input,
-                                      struct gdbarch *gdbarch,
-                                      const struct block *expr_block,
-                                      CORE_ADDR expr_pc);
+  /* Default range checking preference.  The return value from this
+     function provides the automatic setting for 'set check range'.  As a
+     consequence a user is free to override this setting if they want.  */

 
 

-    /* Add fields above this point, so the magic number is always last.  */
-    /* Magic number for compat checking.  */
+  virtual bool range_checking_on_by_default () const
+  { return false; }

 
 

-    long la_magic;
+  /* Is this language case sensitive?  The return value from this function
+     provides the automativ setting for 'set case-sensitive', as a
+     consequence, a user is free to override this setting if they want.  */
+
+  virtual enum case_sensitivity case_sensitivity () const
+  { return case_sensitive_on; }

 
 

-  };

 
 

-#define LANG_MAGIC     910823L
+  /* Multi-dimensional array ordering.  */
+
+  virtual enum array_ordering array_ordering () const
+  { return array_row_major; }
+
+  /* Style of macro expansion, if any, supported by this language.  The
+     default is no macro expansion.  */
+
+  virtual enum macro_expansion macro_expansion () const
+  { return macro_expansion_no; }
+
+  /* Return a structure containing various operations on varobj specific
+     for this language.  */
+
+  virtual const struct lang_varobj_ops *varobj_ops () const;
+
+protected:
+
+  /* This is the overridable part of the GET_SYMBOL_NAME_MATCHER method.
+     See that method for a description of the arguments.  */
+
+  virtual symbol_name_matcher_ftype *get_symbol_name_matcher_inner
+         (const lookup_name_info &lookup_name) const;
+};

 
 /* Pointer to the language_defn for our current language.  This pointer
    always points to *some* valid struct; it can be used without checking
 
 /* Pointer to the language_defn for our current language.  This pointer
    always points to *some* valid struct; it can be used without checking


@@ -457,6 +672,11 @@ extern const struct language_defn *current_language;
 
 extern const struct language_defn *expected_language;
 
 
 extern const struct language_defn *expected_language;
 

+/* Warning issued when current_language and the language of the current
+   frame do not match.  */
+
+extern const char lang_frame_mismatch_warn[];
+

 /* language_mode == 
    language_mode_auto:   current_language automatically set upon selection
    of scope (e.g. stack frame)
 /* language_mode == 
    language_mode_auto:   current_language automatically set upon selection
    of scope (e.g. stack frame)


@@ -468,19 +688,39 @@ extern enum language_mode
   }
 language_mode;
 
   }
 language_mode;
 

+/* Return the type that should be used for booleans for language L in
+   GDBARCH.  */
+

 struct type *language_bool_type (const struct language_defn *l,
                                 struct gdbarch *gdbarch);
 
 struct type *language_bool_type (const struct language_defn *l,
                                 struct gdbarch *gdbarch);
 

+/* Return the type that should be used for characters within a string for
+   language L in GDBARCH.  */
+

 struct type *language_string_char_type (const struct language_defn *l,
                                        struct gdbarch *gdbarch);
 
 struct type *language_string_char_type (const struct language_defn *l,
                                        struct gdbarch *gdbarch);
 

-/* Look up type NAME in language L, and return its definition for architecture
-   GDBARCH.  Returns NULL if not found.  */
+/* Look up a type from the set of OS/ABI specific types defined in
+   GDBARCH for language L.  NAME is used for selecting the matching
+   type, and is passed through to the corresponding
+   lookup_primitive_type member function inside the language_arch_info
+   class.  */

 
 struct type *language_lookup_primitive_type (const struct language_defn *l,
                                             struct gdbarch *gdbarch,
                                             const char *name);
 
 
 struct type *language_lookup_primitive_type (const struct language_defn *l,
                                             struct gdbarch *gdbarch,
                                             const char *name);
 

+/* Look up a type from the set of OS/ABI specific types defined in
+   GDBARCH for language L.  FILTER is used for selecting the matching
+   type, and is passed through to the corresponding
+   lookup_primitive_type member function inside the language_arch_info
+   class.  */
+
+struct type *language_lookup_primitive_type
+  (const struct language_defn *la,
+   struct gdbarch *gdbarch,
+   gdb::function_view<bool (struct type *)> filter);
+

 /* Wrapper around language_lookup_primitive_type to return the
    corresponding symbol.  */
 
 /* Wrapper around language_lookup_primitive_type to return the
    corresponding symbol.  */
 


@@ -502,41 +742,14 @@ struct symbol *
                                  (LANG)->la_language == language_cplus || \
                                  (LANG)->la_language == language_objc)
 
                                  (LANG)->la_language == language_cplus || \
                                  (LANG)->la_language == language_objc)
 

-extern void language_info (int);
+/* Print out the current language settings: language, range and
+   type checking.  */
+
+extern void language_info ();

 
 extern enum language set_language (enum language);
 \f
 
 
 extern enum language set_language (enum language);
 \f
 

-/* This page contains functions that return things that are
-   specific to languages.  Each of these functions is based on
-   the current setting of working_lang, which the user sets
-   with the "set language" command.  */
-
-#define LA_PRINT_TYPE(type,varstring,stream,show,level,flags)          \
-  (current_language->la_print_type(type,varstring,stream,show,level,flags))
-
-#define LA_PRINT_TYPEDEF(type,new_symbol,stream) \
-  (current_language->la_print_typedef(type,new_symbol,stream))
-
-#define LA_VALUE_PRINT(val,stream,options) \
-  (current_language->la_value_print(val,stream,options))
-
-#define LA_PRINT_CHAR(ch, type, stream) \
-  (current_language->la_printchar(ch, type, stream))
-#define LA_PRINT_STRING(stream, elttype, string, length, encoding, force_ellipses, options) \
-  (current_language->la_printstr(stream, elttype, string, length, \
-                                encoding, force_ellipses,options))
-#define LA_EMIT_CHAR(ch, type, stream, quoter) \
-  (current_language->la_emitchar(ch, type, stream, quoter))
-#define LA_GET_STRING(value, buffer, length, chartype, encoding) \
-  (current_language->la_get_string(value, buffer, length, chartype, encoding))
-
-#define LA_PRINT_ARRAY_INDEX(index_value, stream, options) \
-  (current_language->la_print_array_index(index_value, stream, options))
-
-#define LA_ITERATE_OVER_SYMBOLS(BLOCK, NAME, DOMAIN, CALLBACK) \
-  (current_language->la_iterate_over_symbols (BLOCK, NAME, DOMAIN, CALLBACK))
-

 /* Test a character to decide whether it can be printed in literal form
    or needs to be printed in another representation.  For example,
    in C the literal form of the character with octal value 141 is 'a'
 /* Test a character to decide whether it can be printed in literal form
    or needs to be printed in another representation.  For example,
    in C the literal form of the character with octal value 141 is 'a'


@@ -548,21 +761,13 @@ extern enum language set_language (enum language);
    && ((c) < 0x7F || (c) >= 0xA0)      \
    && (!sevenbit_strings || (c) < 0x80))
 
    && ((c) < 0x7F || (c) >= 0xA0)      \
    && (!sevenbit_strings || (c) < 0x80))
 

-/* Type predicates */
-
-extern int pointer_type (struct type *);
-

 /* Error messages */
 
 extern void range_error (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 
 /* Error messages */
 
 extern void range_error (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
 

-/* Data:  Does this value represent "truth" to the current language?  */
-
-extern int value_true (struct value *);
-

 /* Misc:  The string representing a particular enum language.  */
 
 /* Misc:  The string representing a particular enum language.  */
 

-extern enum language language_enum (char *str);
+extern enum language language_enum (const char *str);

 
 extern const struct language_defn *language_def (enum language);
 
 
 extern const struct language_defn *language_def (enum language);
 


@@ -573,65 +778,26 @@ extern const char *language_str (enum language);
 extern CORE_ADDR skip_language_trampoline (struct frame_info *, CORE_ADDR pc);
 
 /* Return demangled language symbol, or NULL.  */
 extern CORE_ADDR skip_language_trampoline (struct frame_info *, CORE_ADDR pc);
 
 /* Return demangled language symbol, or NULL.  */

-extern char *language_demangle (const struct language_defn *current_language, 
-                               const char *mangled, int options);
-
-/* A wrapper for la_sniff_from_mangled_name.  The arguments and result
-   are as for the method.  */
-
-extern int language_sniff_from_mangled_name (const struct language_defn *lang,
-                                            const char *mangled,
-                                            char **demangled);
-
-/* Return class name from physname, or NULL.  */
-extern char *language_class_name_from_physname (const struct language_defn *,
-                                               const char *physname);
-
-/* Splitting strings into words.  */
-extern const char *default_word_break_characters (void);
-
-/* Print the index of an array element using the C99 syntax.  */
-extern void default_print_array_index (struct value *index_value,
-                                       struct ui_file *stream,
-                                      const struct value_print_options *options);
-
-/* Return non-zero if TYPE should be passed (and returned) by
-   reference at the language level.  */
-int language_pass_by_reference (struct type *type);
-
-/* Return zero; by default, types are passed by value at the language
-   level.  The target ABI may pass or return some structs by reference
-   independent of this.  */
-int default_pass_by_reference (struct type *type);
-
-/* The default implementation of la_print_typedef.  */
-void default_print_typedef (struct type *type, struct symbol *new_symbol,
-                           struct ui_file *stream);
-
-void default_get_string (struct value *value, gdb_byte **buffer, int *length,
-                        struct type **char_type, const char **charset);
-
-void c_get_string (struct value *value, gdb_byte **buffer, int *length,
-                  struct type **char_type, const char **charset);
-
-/* The languages supported by GDB.  */
-
-extern const struct language_defn auto_language_defn;
-extern const struct language_defn unknown_language_defn;
-extern const struct language_defn minimal_language_defn;
-
-extern const struct language_defn ada_language_defn;
-extern const struct language_defn asm_language_defn;
-extern const struct language_defn c_language_defn;
-extern const struct language_defn cplus_language_defn;
-extern const struct language_defn d_language_defn;
-extern const struct language_defn f_language_defn;
-extern const struct language_defn go_language_defn;
-extern const struct language_defn m2_language_defn;
-extern const struct language_defn objc_language_defn;
-extern const struct language_defn opencl_language_defn;
-extern const struct language_defn pascal_language_defn;
-extern const struct language_defn rust_language_defn;
+extern gdb::unique_xmalloc_ptr<char> language_demangle
+     (const struct language_defn *current_language,
+      const char *mangled, int options);
+
+/* Return information about whether TYPE should be passed
+   (and returned) by reference at the language level.  */
+struct language_pass_by_ref_info language_pass_by_reference (struct type *type);
+
+void c_get_string (struct value *value,
+                  gdb::unique_xmalloc_ptr<gdb_byte> *buffer,
+                  int *length, struct type **char_type,
+                  const char **charset);
+
+/* Get LANG's symbol_name_matcher method for LOOKUP_NAME.  Returns
+   default_symbol_name_matcher if not set.  LANG is used as a hint;
+   the function may ignore it depending on the current language and
+   LOOKUP_NAME.  Specifically, if the current language is Ada, this
+   may return an Ada matcher regardless of LANG.  */
+symbol_name_matcher_ftype *get_symbol_name_matcher
+  (const language_defn *lang, const lookup_name_info &lookup_name);

 
 /* Save the current language and restore it upon destruction.  */
 
 
 /* Save the current language and restore it upon destruction.  */
 


@@ -659,4 +825,44 @@ private:
   enum language m_lang;
 };
 
   enum language m_lang;
 };
 

+/* If language_mode is language_mode_auto,
+   then switch current language to the language of SYM
+   and restore current language upon destruction.
+
+   Else do nothing.  */
+
+class scoped_switch_to_sym_language_if_auto
+{
+public:
+
+  explicit scoped_switch_to_sym_language_if_auto (const struct symbol *sym)
+  {
+    if (language_mode == language_mode_auto)
+      {
+       m_lang = current_language->la_language;
+       m_switched = true;
+       set_language (sym->language ());
+      }
+    else
+      {
+       m_switched = false;
+       /* Assign to m_lang to silence a GCC warning.  See
+          https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80635.  */
+       m_lang = language_unknown;
+      }
+  }
+
+  ~scoped_switch_to_sym_language_if_auto ()
+  {
+    if (m_switched)
+      set_language (m_lang);
+  }
+
+  DISABLE_COPY_AND_ASSIGN (scoped_switch_to_sym_language_if_auto);
+
+private:
+  bool m_switched;
+  enum language m_lang;
+};
+

 #endif /* defined (LANGUAGE_H) */
 #endif /* defined (LANGUAGE_H) */