From bf6d8a91eac025c21b03d604bdb2e4b901c4c6bc Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Wed, 7 Aug 2013 20:03:52 +0000 Subject: [PATCH] use language of the main symbol With "dwz -m", "main" appears in both the PU and the importing CU when running anon-struct.exp. However, the PU does not have a file name. So, find_main_filename returns the empty string, making deduce_language_from_filename return language_unknown. This patch fixes this problem by changing gdb to use the ordinary symbol-lookup functions to find "main"'s symbol. Then, it examines the symbol's language. I think this is cleaner than the current approach. For one thing it avoids trying to guess the language based on the source file name, instead deferring to the presumably more reliable debuginfo. Another possible fix would have been to change how the file name is found via the "qf" methods. However, I think the approach given is preferable for the reason outlined above. This required a minor test suite change, as now a symtab is expanded during the search for "main". Built and regtested (both ways) on x86-64 Fedora 18. * symfile.c (set_initial_language): Look up "main" symbol and use its language. * symtab.c (find_main_filename): Remove. * symtab.h (find_main_filename): Remove. * gdb.base/maint.exp: Allow zero symtabs to be expanded. --- gdb/ChangeLog | 7 +++++++ gdb/symfile.c | 8 ++++---- gdb/symtab.c | 23 ----------------------- gdb/symtab.h | 2 -- gdb/testsuite/ChangeLog | 4 ++++ gdb/testsuite/gdb.base/maint.exp | 7 ++++--- 6 files changed, 19 insertions(+), 32 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 1097608991..42e60aaed0 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,10 @@ +2013-08-07 Tom Tromey + + * symfile.c (set_initial_language): Look up "main" symbol + and use its language. + * symtab.c (find_main_filename): Remove. + * symtab.h (find_main_filename): Remove. + 2013-08-07 Tom Tromey * dwarf2read.c (recursively_compute_inclusions): Add diff --git a/gdb/symfile.c b/gdb/symfile.c index 3328648755..3dd550927f 100644 --- a/gdb/symfile.c +++ b/gdb/symfile.c @@ -1612,11 +1612,11 @@ set_initial_language (void) lang = language_of_main; else { - const char *filename; + char *name = main_name (); + struct symbol *sym = lookup_symbol (name, NULL, VAR_DOMAIN, NULL); - filename = find_main_filename (); - if (filename != NULL) - lang = deduce_language_from_filename (filename); + if (sym != NULL) + lang = SYMBOL_LANGUAGE (sym); } if (lang == language_unknown) diff --git a/gdb/symtab.c b/gdb/symtab.c index 8076fe5bb3..3bcec238eb 100644 --- a/gdb/symtab.c +++ b/gdb/symtab.c @@ -1949,29 +1949,6 @@ basic_lookup_transparent_type (const char *name) return (struct type *) 0; } -/* Find the name of the file containing main(). */ -/* FIXME: What about languages without main() or specially linked - executables that have no main() ? */ - -const char * -find_main_filename (void) -{ - struct objfile *objfile; - char *name = main_name (); - - ALL_OBJFILES (objfile) - { - const char *result; - - if (!objfile->sf) - continue; - result = objfile->sf->qf->find_symbol_file (objfile, name); - if (result) - return result; - } - return (NULL); -} - /* Search BLOCK for symbol NAME in DOMAIN. Note that if NAME is the demangled form of a C++ symbol, we will fail diff --git a/gdb/symtab.h b/gdb/symtab.h index 6d81507f57..ccf4a4f300 100644 --- a/gdb/symtab.h +++ b/gdb/symtab.h @@ -1252,8 +1252,6 @@ extern VEC (char_ptr) *make_source_files_completion_list (const char *, int matching_obj_sections (struct obj_section *, struct obj_section *); -extern const char *find_main_filename (void); - extern struct symtab *find_line_symtab (struct symtab *, int, int *, int *); extern struct symtab_and_line find_function_start_sal (struct symbol *sym, diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 160a27a87c..fb21761fe7 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2013-08-07 Tom Tromey + + * gdb.base/maint.exp: Allow zero symtabs to be expanded. + 2013-08-07 Tom Tromey * gdb.dwarf2/dwz.exp: New file. diff --git a/gdb/testsuite/gdb.base/maint.exp b/gdb/testsuite/gdb.base/maint.exp index 7057ac7f56..3093aae32c 100644 --- a/gdb/testsuite/gdb.base/maint.exp +++ b/gdb/testsuite/gdb.base/maint.exp @@ -72,9 +72,10 @@ gdb_test "maint print registers" "Name.*Nr.*Rel.*Offset.*Size.*Type.*" gdb_test_no_output "mt set per on" "mt set per on for expand-symtabs" gdb_test_multiple "mt expand-symtabs $subdir/break\[.\]c$" \ "mt expand-symtabs" { - -re "#primary symtabs: (1|2) \\(\[+\](1|2)\\),.*$gdb_prompt $" { - # This should expand one or at most two primary symtabs. - # "Normally" it will expand just the one for break.c, but if the + -re "#primary symtabs: (1|2) \\(\[+\](0|1|2)\\),.*$gdb_prompt $" { + # This should expand at most two primary symtabs. + # "Normally" it will not expand any, because the symtab + # holding "main" will already have been expanded, but if the # file is compiled with -fdebug-types-section then a second primary # symtab for break.c will be created for any types. pass "mt expand-symtabs"