From cb18fd07f2962779c2651adc970541210d4ad98f Mon Sep 17 00:00:00 2001 From: David Malcolm Date: Thu, 18 Aug 2016 18:52:43 +0000 Subject: [PATCH] Spelling suggestions for misspelled preprocessor directives This patch allows the preprocessor to offer suggestions for misspelled directives, taking us from e.g.: test.c:5:2: error: invalid preprocessing directive #endfi #endfi ^~~~~ to: test.c:5:2: error: invalid preprocessing directive #endfi; did you mean #endif? #endfi ^~~~~ endif gcc/c-family/ChangeLog: * c-common.c: Include "spellcheck.h". (cb_get_suggestion): New function. * c-common.h (cb_get_suggestion): New decl. * c-lex.c (init_c_lex): Initialize cb->get_suggestion to cb_get_suggestion. gcc/testsuite/ChangeLog: * gcc.dg/cpp/misspelled-directive-1.c: New testcase. * gcc.dg/cpp/misspelled-directive-2.c: New testcase. libcpp/ChangeLog: * directives.c (directive_names): New array. (_cpp_handle_directive): Offer spelling suggestions for misspelled directives. * errors.c (cpp_diagnostic_at_richloc): New function. (cpp_error_at_richloc): New function. * include/cpplib.h (struct cpp_callbacks): Add field "get_suggestion". (cpp_error_at_richloc): New decl. From-SVN: r239585 --- gcc/c-family/ChangeLog | 8 ++++ gcc/c-family/c-common.c | 17 ++++++++ gcc/c-family/c-common.h | 5 +++ gcc/c-family/c-lex.c | 1 + gcc/testsuite/ChangeLog | 5 +++ .../gcc.dg/cpp/misspelled-directive-1.c | 12 ++++++ .../gcc.dg/cpp/misspelled-directive-2.c | 21 ++++++++++ libcpp/ChangeLog | 11 +++++ libcpp/directives.c | 41 ++++++++++++++++++- libcpp/errors.c | 36 ++++++++++++++++ libcpp/include/cpplib.h | 8 ++++ 11 files changed, 163 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/cpp/misspelled-directive-1.c create mode 100644 gcc/testsuite/gcc.dg/cpp/misspelled-directive-2.c diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog index cc823701fec..1ed5268a91f 100644 --- a/gcc/c-family/ChangeLog +++ b/gcc/c-family/ChangeLog @@ -1,3 +1,11 @@ +2016-08-18 David Malcolm + + * c-common.c: Include "spellcheck.h". + (cb_get_suggestion): New function. + * c-common.h (cb_get_suggestion): New decl. + * c-lex.c (init_c_lex): Initialize cb->get_suggestion to + cb_get_suggestion. + 2016-08-18 Marek Polacek PR c/71514 diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c index 22e3844f43e..9082883cb68 100644 --- a/gcc/c-family/c-common.c +++ b/gcc/c-family/c-common.c @@ -46,6 +46,7 @@ along with GCC; see the file COPYING3. If not see #include "opts.h" #include "gimplify.h" #include "substring-locations.h" +#include "spellcheck.h" cpp_reader *parse_in; /* Declared in c-pragma.h. */ @@ -12948,6 +12949,22 @@ cb_get_source_date_epoch (cpp_reader *pfile ATTRIBUTE_UNUSED) return (time_t) epoch; } +/* Callback for libcpp for offering spelling suggestions for misspelled + directives. GOAL is an unrecognized string; CANDIDATES is a + NULL-terminated array of candidate strings. Return the closest + match to GOAL within CANDIDATES, or NULL if none are good + suggestions. */ + +const char * +cb_get_suggestion (cpp_reader *, const char *goal, + const char *const *candidates) +{ + best_match bm (goal); + while (*candidates) + bm.consider (*candidates++); + return bm.get_best_meaningful_candidate (); +} + /* Check and possibly warn if two declarations have contradictory attributes, such as always_inline vs. noinline. */ diff --git a/gcc/c-family/c-common.h b/gcc/c-family/c-common.h index 4673123fa74..31320bf7c87 100644 --- a/gcc/c-family/c-common.h +++ b/gcc/c-family/c-common.h @@ -1110,6 +1110,11 @@ extern time_t cb_get_source_date_epoch (cpp_reader *pfile); __TIME__ can store. */ #define MAX_SOURCE_DATE_EPOCH HOST_WIDE_INT_C (253402300799) +/* Callback for libcpp for offering spelling suggestions for misspelled + directives. */ +extern const char *cb_get_suggestion (cpp_reader *, const char *, + const char *const *); + extern GTY(()) string_concat_db *g_string_concat_db; /* libcpp can calculate location information about a range of characters diff --git a/gcc/c-family/c-lex.c b/gcc/c-family/c-lex.c index 4c7e3852142..c904ee67fc0 100644 --- a/gcc/c-family/c-lex.c +++ b/gcc/c-family/c-lex.c @@ -81,6 +81,7 @@ init_c_lex (void) cb->read_pch = c_common_read_pch; cb->has_attribute = c_common_has_attribute; cb->get_source_date_epoch = cb_get_source_date_epoch; + cb->get_suggestion = cb_get_suggestion; /* Set the debug callbacks if we can use them. */ if ((debug_info_level == DINFO_LEVEL_VERBOSE diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index e37bff498e4..21e97704db6 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2016-08-18 David Malcolm + + * gcc.dg/cpp/misspelled-directive-1.c: New testcase. + * gcc.dg/cpp/misspelled-directive-2.c: New testcase. + 2016-08-18 Marek Polacek PR c/71514 diff --git a/gcc/testsuite/gcc.dg/cpp/misspelled-directive-1.c b/gcc/testsuite/gcc.dg/cpp/misspelled-directive-1.c new file mode 100644 index 00000000000..f79670a17cb --- /dev/null +++ b/gcc/testsuite/gcc.dg/cpp/misspelled-directive-1.c @@ -0,0 +1,12 @@ +#ifndef SOME_GUARD /* { dg-error "unterminated" } */ + +#if 1 +/* Typo here: "endfi" should have been "endif". */ +#endfi /* { dg-error "invalid preprocessing directive #endfi; did you mean #endif?" } */ + +int make_non_empty; + +/* Another transposition typo: */ +#deifne FOO /* { dg-error "invalid preprocessing directive #deifne; did you mean #define?" } */ + +#endif /* #ifndef SOME_GUARD */ diff --git a/gcc/testsuite/gcc.dg/cpp/misspelled-directive-2.c b/gcc/testsuite/gcc.dg/cpp/misspelled-directive-2.c new file mode 100644 index 00000000000..7ec5dee9024 --- /dev/null +++ b/gcc/testsuite/gcc.dg/cpp/misspelled-directive-2.c @@ -0,0 +1,21 @@ +/* { dg-options "-fdiagnostics-show-caret" } */ + +#endfi /* { dg-error "invalid preprocessing directive #endfi; did you mean #endif?" } */ + +/* Verify that we offer fix-it hints. */ +/* { dg-begin-multiline-output "" } + #endfi + ^~~~~ + endif + { dg-end-multiline-output "" } */ + +/* Test coverage for the case of an unrecognized directive where no suggestion + is offered. */ + +#this_does_not_match_anything /* { dg-error "invalid preprocessing directive #this_does_not_match_anything" } */ +/* { dg-begin-multiline-output "" } + #this_does_not_match_anything + ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ + { dg-end-multiline-output "" } */ + +int make_non_empty; diff --git a/libcpp/ChangeLog b/libcpp/ChangeLog index e700dfe31e0..5d4a09450e0 100644 --- a/libcpp/ChangeLog +++ b/libcpp/ChangeLog @@ -1,3 +1,14 @@ +2016-08-18 David Malcolm + + * directives.c (directive_names): New array. + (_cpp_handle_directive): Offer spelling suggestions for misspelled + directives. + * errors.c (cpp_diagnostic_at_richloc): New function. + (cpp_error_at_richloc): New function. + * include/cpplib.h (struct cpp_callbacks): Add field + "get_suggestion". + (cpp_error_at_richloc): New decl. + 2016-08-18 Marek Polacek PR c/7652 diff --git a/libcpp/directives.c b/libcpp/directives.c index 772b835804b..c0006a49cc4 100644 --- a/libcpp/directives.c +++ b/libcpp/directives.c @@ -188,6 +188,16 @@ static const directive dtable[] = DIRECTIVE_TABLE }; #undef D + +/* A NULL-terminated array of directive names for use + when suggesting corrections for misspelled directives. */ +#define D(name, t, origin, flags) #name, +static const char * const directive_names[] = { +DIRECTIVE_TABLE + NULL +}; +#undef D + #undef DIRECTIVE_TABLE /* Wrapper struct directive for linemarkers. @@ -498,8 +508,35 @@ _cpp_handle_directive (cpp_reader *pfile, int indented) if (CPP_OPTION (pfile, lang) == CLK_ASM) skip = 0; else if (!pfile->state.skipping) - cpp_error (pfile, CPP_DL_ERROR, "invalid preprocessing directive #%s", - cpp_token_as_text (pfile, dname)); + { + const char *unrecognized + = (const char *)cpp_token_as_text (pfile, dname); + const char *hint = NULL; + + /* Call back into gcc to get a spelling suggestion. Ideally + we'd just use best_match from gcc/spellcheck.h (and filter + out the uncommon directives), but that requires moving it + to a support library. */ + if (pfile->cb.get_suggestion) + hint = pfile->cb.get_suggestion (pfile, unrecognized, + directive_names); + + if (hint) + { + rich_location richloc (pfile->line_table, dname->src_loc); + source_range misspelled_token_range + = get_range_from_loc (pfile->line_table, dname->src_loc); + richloc.add_fixit_replace (misspelled_token_range, hint); + cpp_error_at_richloc (pfile, CPP_DL_ERROR, &richloc, + "invalid preprocessing directive #%s;" + " did you mean #%s?", + unrecognized, hint); + } + else + cpp_error (pfile, CPP_DL_ERROR, + "invalid preprocessing directive #%s", + unrecognized); + } } pfile->directive = dir; diff --git a/libcpp/errors.c b/libcpp/errors.c index f7d411226ee..3b0a0b41461 100644 --- a/libcpp/errors.c +++ b/libcpp/errors.c @@ -29,6 +29,23 @@ along with this program; see the file COPYING3. If not see /* Print a diagnostic at the given location. */ +ATTRIBUTE_FPTR_PRINTF(5,0) +static bool +cpp_diagnostic_at_richloc (cpp_reader * pfile, int level, int reason, + rich_location *richloc, + const char *msgid, va_list *ap) +{ + bool ret; + + if (!pfile->cb.error) + abort (); + ret = pfile->cb.error (pfile, level, reason, richloc, _(msgid), ap); + + return ret; +} + +/* Print a diagnostic at the given location. */ + ATTRIBUTE_FPTR_PRINTF(5,0) static bool cpp_diagnostic_at (cpp_reader * pfile, int level, int reason, @@ -255,6 +272,25 @@ cpp_error_at (cpp_reader * pfile, int level, source_location src_loc, return ret; } +/* As cpp_error, but use RICHLOC as the location of the error, without + a column override. */ + +bool +cpp_error_at_richloc (cpp_reader * pfile, int level, rich_location *richloc, + const char *msgid, ...) +{ + va_list ap; + bool ret; + + va_start (ap, msgid); + + ret = cpp_diagnostic_at_richloc (pfile, level, CPP_W_NONE, richloc, + msgid, &ap); + + va_end (ap); + return ret; +} + /* Print a warning or error, depending on the value of LEVEL. Include information from errno. */ diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h index 659686bf261..a497811eec0 100644 --- a/libcpp/include/cpplib.h +++ b/libcpp/include/cpplib.h @@ -597,6 +597,9 @@ struct cpp_callbacks /* Callback to parse SOURCE_DATE_EPOCH from environment. */ time_t (*get_source_date_epoch) (cpp_reader *); + + /* Callback for providing suggestions for misspelled directives. */ + const char *(*get_suggestion) (cpp_reader *, const char *, const char *const *); }; #ifdef VMS @@ -1066,6 +1069,11 @@ extern bool cpp_error_at (cpp_reader * pfile, int level, source_location src_loc, const char *msgid, ...) ATTRIBUTE_PRINTF_4; +extern bool cpp_error_at_richloc (cpp_reader * pfile, int level, + rich_location *richloc, const char *msgid, + ...) + ATTRIBUTE_PRINTF_4; + /* In lex.c */ extern int cpp_ideq (const cpp_token *, const char *); extern void cpp_output_line (cpp_reader *, FILE *); -- 2.30.2