On Thu, May 16, 2019 at 11:20 AM Thomas De Schampheleire
<patrickdeping...@gmail.com> wrote:
>
> From: Thomas De Schampheleire <thomas.de_schamphele...@nokia.com>
>
> In addition to making -feliminate-unused-debug-symbols work for the DWARF
> format (see [1]), make this option the default. This behavior was the case
> before, e.g. under gcc 4.9.x.
> [1] https://gcc.gnu.org/viewcvs/gcc?view=revision&revision=269925
I have tested this patch and it causes a few FAILs, eventually hinting
at implementation issues:
=== g++ tests ===
Running target unix
FAIL: g++.dg/debug/enum-2.C -gstabs -O2 scan-assembler JTI_MAX
FAIL: g++.dg/debug/enum-2.C -gstabs -O3 scan-assembler JTI_MAX
FAIL: g++.dg/debug/enum-2.C -gstabs+ -O2 scan-assembler JTI_MAX
FAIL: g++.dg/debug/enum-2.C -gstabs+ -O3 scan-assembler JTI_MAX
FAIL: g++.dg/debug/enum-2.C -gstabs+3 -O2 scan-assembler JTI_MAX
FAIL: g++.dg/debug/enum-2.C -gstabs+3 -O3 scan-assembler JTI_MAX
FAIL: g++.dg/debug/enum-2.C -gstabs3 -O2 scan-assembler JTI_MAX
FAIL: g++.dg/debug/enum-2.C -gstabs3 -O3 scan-assembler JTI_MAX
maybe expected (stabs....)
FAIL: g++.dg/debug/dwarf2/fesd-any.C -std=gnu++14 scan-assembler field_head_or
dy_defn_fld_head.*DW_AT_name
FAIL: g++.dg/debug/dwarf2/fesd-any.C -std=gnu++14 scan-assembler field_head_or
dy_defn_ptr_head.*DW_AT_name
FAIL: g++.dg/debug/dwarf2/fesd-any.C -std=gnu++14 scan-assembler field_head_or
dy_defn_ref_head.*DW_AT_name
FAIL: g++.dg/debug/dwarf2/fesd-any.C -std=gnu++14 scan-assembler field_head_or
dy_defn_var_head_fld.*DW_AT_name
... more ...
FAIL: g++.dg/debug/dwarf2/fesd-baseonly.C -std=gnu++14 scan-assembler gstruct_
head_ordy_defn_var_head.*DW_AT_name
FAIL: g++.dg/debug/dwarf2/fesd-baseonly.C -std=gnu++14 scan-assembler gstruct_
head_tmpl_defn_var_head<int>.*DW_AT_name
FAIL: g++.dg/debug/dwarf2/fesd-baseonly.C -std=gnu++17 scan-assembler gstruct_
head_ordy_defn_var_head.*DW_AT_name
FAIL: g++.dg/debug/dwarf2/fesd-baseonly.C -std=gnu++17 scan-assembler gstruct_
head_tmpl_defn_var_head<int>.*DW_AT_name
FAIL: g++.dg/debug/dwarf2/fesd-baseonly.C -std=gnu++98 scan-assembler gstruct_
head_ordy_defn_var_head.*DW_AT_name
FAIL: g++.dg/debug/dwarf2/fesd-baseonly.C -std=gnu++98
scan-assembler gstruct_head_tmpl_defn_var_head<int>.*DW_AT_name
FAIL: g++.dg/debug/dwarf2/fesd-none.C -std=gnu++14 scan-assembler
gstruct_head_ordy_defn_var_head.*DW_AT_name
FAIL: g++.dg/debug/dwarf2/fesd-none.C -std=gnu++14 scan-assembler
gstruct_head_tmpl_defn_var_head<int>.*DW_AT_name
... more fesd-* testcases FAIL ...
FAIL: g++.dg/debug/dwarf2/inline-var-1.C -std=gnu++17
scan-assembler-times DW_AT_[^\\n\\r]*linkage_name 7
FAIL: g++.dg/debug/dwarf2/inline-var-1.C -std=gnu++17
scan-assembler-times DW_AT_specification 6
FAIL: g++.dg/debug/dwarf2/inline-var-1.C -std=gnu++17
scan-assembler-times 0x3[^\\n\\r]* DW_AT_inline 6
C variants of the fesd-* testcases also FAIL. Those testcases are
huge, a quick look didn't
reveal whether those are expected FAILs or not.
Richard.
> gcc/ChangeLog:
>
> 2019-05-16 Thomas De Schampheleire <thomas.de_schamphele...@nokia.com>
>
> PR debug/86964
> * common.opt (feliminate-unused-debug-symbols): Enable by default.
> * doc/invoke.texi (Debugging Options): Document new default of
> -feliminate-unused-debug-symbols and remove restriction to 'stabs'.
> ---
> gcc/common.opt | 2 +-
> gcc/doc/invoke.texi | 9 +++++----
> 2 files changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/gcc/common.opt b/gcc/common.opt
> index d342c4f3749..0e72fd08ec4 100644
> --- a/gcc/common.opt
> +++ b/gcc/common.opt
> @@ -1379,7 +1379,7 @@ Common Report Var(flag_ipa_sra) Init(0) Optimization
> Perform interprocedural reduction of aggregates.
>
> feliminate-unused-debug-symbols
> -Common Report Var(flag_debug_only_used_symbols)
> +Common Report Var(flag_debug_only_used_symbols) Init(1)
> Perform unused symbol elimination in debug info.
>
> feliminate-unused-debug-types
> diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
> index 5e3e8873d35..06c8c60f19e 100644
> --- a/gcc/doc/invoke.texi
> +++ b/gcc/doc/invoke.texi
> @@ -388,7 +388,7 @@ Objective-C and Objective-C++ Dialects}.
> -fno-eliminate-unused-debug-types @gol
> -femit-struct-debug-baseonly -femit-struct-debug-reduced @gol
> -femit-struct-debug-detailed@r{[}=@var{spec-list}@r{]} @gol
> --feliminate-unused-debug-symbols -femit-class-debug-always @gol
> +-fno-eliminate-unused-debug-symbols -femit-class-debug-always @gol
> -fno-merge-debug-strings -fno-dwarf2-cfi-asm @gol
> -fvar-tracking -fvar-tracking-assignments}
>
> @@ -7827,10 +7827,11 @@ confusion with @option{-gdwarf-@var{level}}.
> Instead use an additional @option{-g@var{level}} option to change the
> debug level for DWARF.
>
> -@item -feliminate-unused-debug-symbols
> +@item -fno-eliminate-unused-debug-symbols
> @opindex feliminate-unused-debug-symbols
> -Produce debugging information in stabs format (if that is supported),
> -for only symbols that are actually used.
> +@opindex fno-eliminate-unused-debug-symbols
> +By default, no debug information is produced for symbols that are not
> actually
> +used. Use this option if you want debug information for all symbols.
>
> @item -femit-class-debug-always
> @opindex femit-class-debug-always
> --
> 2.21.0
>
