2007-10-13 Pedro Alves * gdbarch.sh (gdbarch_skip___main_call): New. * gdbarch.h, gdbarch.c: Regenerate. * i386-tdep.h (i386_skip___main_call): Declare. * i386-tdep.c (i386_skip___main_call): New. * i386-cygwin-tdep.c (i386_cygwin_init_abi): Register i386_skip___main_call as gdbarch_skip___main_call gdbarch callback. * symtab.c (find_function_start_sal): When pc points at the "main" function, call gdbarch_skip___main_call. --- gdb/gdbarch.c | 33 +++++++++++++++++++++++++++++++++ gdb/gdbarch.h | 6 ++++++ gdb/gdbarch.sh | 1 + gdb/i386-cygwin-tdep.c | 2 ++ gdb/i386-tdep.c | 27 +++++++++++++++++++++++++++ gdb/i386-tdep.h | 1 + gdb/symtab.c | 15 +++++++++++++++ 7 files changed, 85 insertions(+) Index: src/gdb/i386-tdep.c =================================================================== --- src.orig/gdb/i386-tdep.c 2008-01-29 04:39:24.000000000 +0000 +++ src/gdb/i386-tdep.c 2008-01-29 04:39:40.000000000 +0000 @@ -949,6 +949,33 @@ i386_skip_prologue (struct gdbarch *gdba return pc; } +/* Check that the code pointed to by PC corresponds to a call to + __main, skip it if so. Return PC otherwise. */ + +CORE_ADDR +i386_skip___main_call (struct gdbarch *gdbarch, CORE_ADDR pc) +{ + gdb_byte op; + + read_memory_nobpt (pc, &op, 1); + if (op == 0xe8) + { + gdb_byte buf[4]; + if (target_read_memory (pc + 1, buf, sizeof buf) == 0) + { + CORE_ADDR call_dest = pc + 5 + extract_unsigned_integer (buf, 4); + + struct minimal_symbol *s = lookup_minimal_symbol_by_pc (call_dest); + if (s != NULL + && SYMBOL_LINKAGE_NAME (s) != NULL + && strcmp (SYMBOL_LINKAGE_NAME (s), "__main") == 0) + pc += 5; + } + } + + return pc; +} + /* This function is 64-bit safe. */ static CORE_ADDR Index: src/gdb/gdbarch.c =================================================================== --- src.orig/gdb/gdbarch.c 2008-01-29 04:39:16.000000000 +0000 +++ src/gdb/gdbarch.c 2008-01-29 04:39:40.000000000 +0000 @@ -184,6 +184,7 @@ struct gdbarch gdbarch_integer_to_address_ftype *integer_to_address; gdbarch_return_value_ftype *return_value; gdbarch_skip_prologue_ftype *skip_prologue; + gdbarch_skip___main_call_ftype *skip___main_call; gdbarch_inner_than_ftype *inner_than; gdbarch_breakpoint_from_pc_ftype *breakpoint_from_pc; gdbarch_adjust_breakpoint_address_ftype *adjust_breakpoint_address; @@ -306,6 +307,7 @@ struct gdbarch startup_gdbarch = 0, /* integer_to_address */ 0, /* return_value */ 0, /* skip_prologue */ + 0, /* skip___main_call */ 0, /* inner_than */ 0, /* breakpoint_from_pc */ 0, /* adjust_breakpoint_address */ @@ -542,6 +544,7 @@ verify_gdbarch (struct gdbarch *gdbarch) /* Skip verify of return_value, has predicate */ if (gdbarch->skip_prologue == 0) fprintf_unfiltered (log, "\n\tskip_prologue"); + /* Skip verify of skip___main_call, has predicate */ if (gdbarch->inner_than == 0) fprintf_unfiltered (log, "\n\tinner_than"); if (gdbarch->breakpoint_from_pc == 0) @@ -934,6 +937,12 @@ gdbarch_dump (struct gdbarch *gdbarch, s "gdbarch_dump: single_step_through_delay = <0x%lx>\n", (long) gdbarch->single_step_through_delay); fprintf_unfiltered (file, + "gdbarch_dump: gdbarch_skip___main_call_p() = %d\n", + gdbarch_skip___main_call_p (gdbarch)); + fprintf_unfiltered (file, + "gdbarch_dump: skip___main_call = <0x%lx>\n", + (long) gdbarch->skip___main_call); + fprintf_unfiltered (file, "gdbarch_dump: gdbarch_skip_permanent_breakpoint_p() = %d\n", gdbarch_skip_permanent_breakpoint_p (gdbarch)); fprintf_unfiltered (file, @@ -2075,6 +2084,30 @@ set_gdbarch_skip_prologue (struct gdbarc } int +gdbarch_skip___main_call_p (struct gdbarch *gdbarch) +{ + gdb_assert (gdbarch != NULL); + return gdbarch->skip___main_call != NULL; +} + +CORE_ADDR +gdbarch_skip___main_call (struct gdbarch *gdbarch, CORE_ADDR ip) +{ + gdb_assert (gdbarch != NULL); + gdb_assert (gdbarch->skip___main_call != NULL); + if (gdbarch_debug >= 2) + fprintf_unfiltered (gdb_stdlog, "gdbarch_skip___main_call called\n"); + return gdbarch->skip___main_call (gdbarch, ip); +} + +void +set_gdbarch_skip___main_call (struct gdbarch *gdbarch, + gdbarch_skip___main_call_ftype skip___main_call) +{ + gdbarch->skip___main_call = skip___main_call; +} + +int gdbarch_inner_than (struct gdbarch *gdbarch, CORE_ADDR lhs, CORE_ADDR rhs) { gdb_assert (gdbarch != NULL); Index: src/gdb/gdbarch.h =================================================================== --- src.orig/gdb/gdbarch.h 2008-01-29 04:39:16.000000000 +0000 +++ src/gdb/gdbarch.h 2008-01-29 04:39:40.000000000 +0000 @@ -374,6 +374,12 @@ typedef CORE_ADDR (gdbarch_skip_prologue extern CORE_ADDR gdbarch_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR ip); extern void set_gdbarch_skip_prologue (struct gdbarch *gdbarch, gdbarch_skip_prologue_ftype *skip_prologue); +extern int gdbarch_skip___main_call_p (struct gdbarch *gdbarch); + +typedef CORE_ADDR (gdbarch_skip___main_call_ftype) (struct gdbarch *gdbarch, CORE_ADDR ip); +extern CORE_ADDR gdbarch_skip___main_call (struct gdbarch *gdbarch, CORE_ADDR ip); +extern void set_gdbarch_skip___main_call (struct gdbarch *gdbarch, gdbarch_skip___main_call_ftype *skip___main_call); + typedef int (gdbarch_inner_than_ftype) (CORE_ADDR lhs, CORE_ADDR rhs); extern int gdbarch_inner_than (struct gdbarch *gdbarch, CORE_ADDR lhs, CORE_ADDR rhs); extern void set_gdbarch_inner_than (struct gdbarch *gdbarch, gdbarch_inner_than_ftype *inner_than); Index: src/gdb/gdbarch.sh =================================================================== --- src.orig/gdb/gdbarch.sh 2008-01-29 04:39:16.000000000 +0000 +++ src/gdb/gdbarch.sh 2008-01-29 04:39:40.000000000 +0000 @@ -477,6 +477,7 @@ M:CORE_ADDR:integer_to_address:struct ty M:enum return_value_convention:return_value:struct type *valtype, struct regcache *regcache, gdb_byte *readbuf, const gdb_byte *writebuf:valtype, regcache, readbuf, writebuf m:CORE_ADDR:skip_prologue:CORE_ADDR ip:ip:0:0 +M:CORE_ADDR:skip___main_call:CORE_ADDR ip:ip f:int:inner_than:CORE_ADDR lhs, CORE_ADDR rhs:lhs, rhs:0:0 m:const gdb_byte *:breakpoint_from_pc:CORE_ADDR *pcptr, int *lenptr:pcptr, lenptr::0: M:CORE_ADDR:adjust_breakpoint_address:CORE_ADDR bpaddr:bpaddr Index: src/gdb/i386-cygwin-tdep.c =================================================================== --- src.orig/gdb/i386-cygwin-tdep.c 2008-01-29 04:39:18.000000000 +0000 +++ src/gdb/i386-cygwin-tdep.c 2008-01-29 04:39:40.000000000 +0000 @@ -227,6 +227,8 @@ i386_cygwin_init_abi (struct gdbarch_inf set_gdbarch_skip_trampoline_code (gdbarch, i386_cygwin_skip_trampoline_code); + set_gdbarch_skip___main_call (gdbarch, i386_skip___main_call); + tdep->struct_return = reg_struct_return; tdep->gregset_reg_offset = i386_win32_gregset_reg_offset; Index: src/gdb/i386-tdep.h =================================================================== --- src.orig/gdb/i386-tdep.h 2008-01-29 04:39:18.000000000 +0000 +++ src/gdb/i386-tdep.h 2008-01-29 04:39:40.000000000 +0000 @@ -166,6 +166,7 @@ extern struct type *i386_sse_type (struc /* Functions exported from i386-tdep.c. */ extern CORE_ADDR i386_pe_skip_trampoline_code (CORE_ADDR pc, char *name); +extern CORE_ADDR i386_skip___main_call (struct gdbarch *gdbarch, CORE_ADDR pc); /* Return the name of register REGNUM. */ extern char const *i386_register_name (struct gdbarch * gdbarch, int regnum); Index: src/gdb/symtab.c =================================================================== --- src.orig/gdb/symtab.c 2008-01-29 04:39:16.000000000 +0000 +++ src/gdb/symtab.c 2008-01-29 04:39:40.000000000 +0000 @@ -2506,6 +2506,21 @@ find_function_start_sal (struct symbol * /* Recalculate the line number (might not be N+1). */ sal = find_pc_sect_line (pc, SYMBOL_BFD_SECTION (sym), 0); } + + /* On targets with executable formats that don't have a concept of + constructors (ELF with .init has, PE doesn't), gcc emits a call + to `__main' in `main' between the prologue and before user + code. */ + if (funfirstline + && gdbarch_skip___main_call_p (current_gdbarch) + && SYMBOL_LINKAGE_NAME (sym) + && strcmp (SYMBOL_LINKAGE_NAME (sym), "main") == 0) + { + pc = gdbarch_skip___main_call (current_gdbarch, pc); + /* Recalculate the line number (might not be N+1). */ + sal = find_pc_sect_line (pc, SYMBOL_BFD_SECTION (sym), 0); + } + sal.pc = pc; return sal;