From 49e607f511c1fab82a0116990a72d1915c74bb4a Mon Sep 17 00:00:00 2001 From: Stephan Rohr Date: Sat, 3 Aug 2024 02:07:42 -0700 Subject: [PATCH] gdb: adjust the default place of 'list' to main's prologue The 'list' command prints around the 'main' function if the current source location is not set. The prologue of 'main' is skipped and the first real line of 'main' is offset by 'lines_to_print - 1'. This is incorrect, the location should be defaulted to main's prologue without applying offsets (similar to 'list main'). Printing around the selected line is then done in 'list_around_line'. The patch also fixes an issue if the list command is used before the program is started. For example, with the following code: 26 static void attribute ((used)) ambiguous_fun (void) {} 27 28 static int attribute ((used)) ambiguous_var; 29 30 31 32 33 34 35 36 37 38 int 39 main (void) 40 { 41 return 0; 42 } GDB offsets the relevant line by 'lines_to_print - 1' and then by another 'lines_to_print / 2' and prints: (gdb) list 27 28 static int attribute ((used)) ambiguous_var; 29 30 31 32 33 34 35 36 With this patch, GDB correctly prints: 37 38 int 39 main (void) 40 { 41 return 0; 42 } Approved-By: Andrew Burgess --- gdb/source.c | 4 +-- gdb/testsuite/gdb.base/cursal.c | 2 +- gdb/testsuite/gdb.base/cursal.exp | 4 +-- gdb/testsuite/gdb.base/list-ambiguous0.c | 2 +- gdb/testsuite/gdb.base/list-before-start.exp | 36 ++++++++++++++++++++ gdb/testsuite/gdb.mi/mi-file.exp | 10 ++---- 6 files changed, 44 insertions(+), 14 deletions(-) create mode 100644 gdb/testsuite/gdb.base/list-before-start.exp diff --git a/gdb/source.c b/gdb/source.c index 25d6e7183a7..0c5c2bad819 100644 --- a/gdb/source.c +++ b/gdb/source.c @@ -319,13 +319,13 @@ select_source_symtab () SEARCH_FUNCTION_DOMAIN, nullptr); if (bsym.symbol != nullptr) { - symtab_and_line sal = find_function_start_sal (bsym.symbol, true); + symtab_and_line sal = find_function_start_sal (bsym.symbol, false); if (sal.symtab == NULL) /* We couldn't find the location of `main', possibly due to missing line number info, fall back to line 1 in the corresponding file. */ loc->set (bsym.symbol->symtab (), 1); else - loc->set (sal.symtab, std::max (sal.line - (lines_to_list - 1), 1)); + loc->set (sal.symtab, sal.line); return; } diff --git a/gdb/testsuite/gdb.base/cursal.c b/gdb/testsuite/gdb.base/cursal.c index 8dc713f3541..bc1e46f0e4c 100644 --- a/gdb/testsuite/gdb.base/cursal.c +++ b/gdb/testsuite/gdb.base/cursal.c @@ -31,7 +31,7 @@ func1 () int main () -{ +{ /* main prologue */ int v0 = 0; func1 (); diff --git a/gdb/testsuite/gdb.base/cursal.exp b/gdb/testsuite/gdb.base/cursal.exp index 3acced86e3c..6c1fe3812be 100644 --- a/gdb/testsuite/gdb.base/cursal.exp +++ b/gdb/testsuite/gdb.base/cursal.exp @@ -25,9 +25,9 @@ clean_restart gdb_file_cmd ${binfile} gdb_test_no_output "set listsize 1" -# initial sal should be first statement in main +# initial sal should be main's prologue. gdb_test "list" \ - "v0 = 0;" \ + "{ /\\* main prologue \\*/" \ "list before run" gdb_load ${binfile} diff --git a/gdb/testsuite/gdb.base/list-ambiguous0.c b/gdb/testsuite/gdb.base/list-ambiguous0.c index cff16e583de..db11702a5b0 100644 --- a/gdb/testsuite/gdb.base/list-ambiguous0.c +++ b/gdb/testsuite/gdb.base/list-ambiguous0.c @@ -37,6 +37,6 @@ static int __attribute__ ((used)) ambiguous_var; int main (void) -{ +{ /* main prologue */ return 0; } diff --git a/gdb/testsuite/gdb.base/list-before-start.exp b/gdb/testsuite/gdb.base/list-before-start.exp new file mode 100644 index 00000000000..54992573316 --- /dev/null +++ b/gdb/testsuite/gdb.base/list-before-start.exp @@ -0,0 +1,36 @@ +# Copyright 2024 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +# Test the "list" command to print the location around main before the +# program is started. + +standard_testfile list-ambiguous0.c + +if {[prepare_for_testing "failed to prepare" $testfile $srcfile debug]} { + return -1 +} + +set fill "${decimal}\\s+\[^\n\r\]+" + +gdb_test_no_output "set listsize 10" + +gdb_test "list" \ + [multi_line \ + "${decimal}\\s+" \ + "${decimal}\\s+int" \ + "${decimal}\\s+main\[^\n\r\]+" \ + "${decimal}\\s+\\{ /\\* main prologue \\*/" \ + "${fill}" \ + "${fill}" ] diff --git a/gdb/testsuite/gdb.mi/mi-file.exp b/gdb/testsuite/gdb.mi/mi-file.exp index 8e404f9c9bd..00d28886252 100644 --- a/gdb/testsuite/gdb.mi/mi-file.exp +++ b/gdb/testsuite/gdb.mi/mi-file.exp @@ -42,16 +42,10 @@ proc test_file_list_exec_source_file {} { } # get the path and absolute path to the current executable - # - # In gdb 6.2 (at least), the default line number is set by - # select_source_symtab to the first line of "main" minus - # the value of "lines_to_list" (which defaults to 10) plus one. - # --chastain 2004-08-13 set line_main_head [gdb_get_line_number "main ("] - set line_main_body [expr $line_main_head + 2] - set gdb_lines_to_list 10 - set line_default [expr $line_main_body - $gdb_lines_to_list + 1] + set line_main_prologue [expr $line_main_head + 1] + set line_default $line_main_prologue mi_gdb_test "111-file-list-exec-source-file" \ "111\\\^done,line=\"$line_default\",file=\"${srcfilepath}\",fullname=\"$fullname_syntax${srcfile}\",macro-info=\"0\"" \ -- 2.39.5