From 87b647cfb13a47effebe185b7dcc733b45f51789 Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Fri, 28 Apr 2023 08:38:38 -0600 Subject: [PATCH] Add PARSER_LEAVE_BLOCK_ALONE flag This adds a PARSER_LEAVE_BLOCK_ALONE flag, and changes the parse API to respect it. This flag lets callers avoid any change to the passed-in block and expression PC, letting them specify the context exactly. In particular, now nullptr can be used to indicate that the parse should not examine any local variables. --- gdb/expression.h | 6 ++++++ gdb/parse.c | 37 +++++++++++++++++++++---------------- 2 files changed, 27 insertions(+), 16 deletions(-) diff --git a/gdb/expression.h b/gdb/expression.h index c485b159ef8..d1858776e8e 100644 --- a/gdb/expression.h +++ b/gdb/expression.h @@ -301,6 +301,12 @@ enum parser_flag it parses. For yacc-based parsers, this translates to setting yydebug. */ PARSER_DEBUG = (1 << 2), + + /* Normally the expression-parsing functions like parse_exp_1 will + attempt to find a context block if one is not passed in. If set, + this flag suppresses this search and uses a null context for the + parse. */ + PARSER_LEAVE_BLOCK_ALONE = (1 << 3), }; DEF_ENUM_FLAGS_TYPE (enum parser_flag, parser_flags); diff --git a/gdb/parse.c b/gdb/parse.c index bbe5cf12d37..221733a3f90 100644 --- a/gdb/parse.c +++ b/gdb/parse.c @@ -344,26 +344,31 @@ parse_exp_in_context (const char **stringptr, CORE_ADDR pc, if (tracker == nullptr) tracker = &local_tracker; - /* If no context specified, try using the current frame, if any. */ - if (!expression_context_block) - expression_context_block = get_selected_block (&expression_context_pc); - else if (pc == 0) - expression_context_pc = expression_context_block->entry_pc (); - else - expression_context_pc = pc; + if ((flags & PARSER_LEAVE_BLOCK_ALONE) == 0) + { + /* If no context specified, try using the current frame, if any. */ + if (!expression_context_block) + expression_context_block + = get_selected_block (&expression_context_pc); + else if (pc == 0) + expression_context_pc = expression_context_block->entry_pc (); + else + expression_context_pc = pc; - /* Fall back to using the current source static context, if any. */ + /* Fall back to using the current source static context, if any. */ - if (!expression_context_block) - { - struct symtab_and_line cursal = get_current_source_symtab_and_line (); + if (!expression_context_block) + { + struct symtab_and_line cursal + = get_current_source_symtab_and_line (); - if (cursal.symtab) - expression_context_block - = cursal.symtab->compunit ()->blockvector ()->static_block (); + if (cursal.symtab) + expression_context_block + = cursal.symtab->compunit ()->blockvector ()->static_block (); - if (expression_context_block) - expression_context_pc = expression_context_block->entry_pc (); + if (expression_context_block) + expression_context_pc = expression_context_block->entry_pc (); + } } if (language_mode == language_mode_auto && block != NULL) -- 2.30.2