Hi all,
As reported here, https://gcc.gnu.org/ml/gcc-help/2020-02/msg00062.html,
GCC does not behave according to manual when `-gdwarf -g1` options are
used; it does not generate the debugging information for external
variables even though it is supposed to (and it does so for other
debugging formats):
aneyman@supox:/tmp$ cat foo.c
int foo __attribute__((externally_visible));
aneyman@supox:/tmp$ gcc -c -O2 -gdwarf -g1 foo.c
aneyman@supox:/tmp$ readelf -wi foo.o
aneyman@supox:/tmp$ gcc -c -O2 -gdwarf -g2 foo.c
aneyman@supox:/tmp$ readelf -wi foo.o
...
<1><1d>: Abbrev Number: 2 (DW_TAG_variable)
<1e> DW_AT_name : foo
The attached patch fixes this issue.
Regards,
Alexey.
>From a4cdccf633c83746481daac5da088b07843c6c38 Mon Sep 17 00:00:00 2001
From: Alexey Neyman <sti...@att.net>
Date: Thu, 13 Feb 2020 22:01:10 -0800
Subject: [PATCH] debug/93751 Create DIEs for external vars with -g1
-g1 is described in the manual to generate debug info for functions and
external variables. It does that for older debugging formats but not for
DWARF. This change aligns the behavior of `-gdwarf -g1` with the
description in the manual.
2020-02-14 Alexey Neyman <sti...@att.net>
PR debug/93751
* dwarf2out.c (gen_decl_die): Proceed to generating the DIE if
the debug level is terse and the declaration is public.
(dwarf2out_decl): Same.
Signed-off-by: Alexey Neyman <sti...@att.net>
---
gcc/dwarf2out.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index fe46c7e1eee..5f9e82a8da2 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -26354,8 +26354,10 @@ gen_decl_die (tree decl, tree origin, struct vlr_context *ctx,
case VAR_DECL:
case RESULT_DECL:
/* If we are in terse mode, don't generate any DIEs to represent any
- variable declarations or definitions. */
- if (debug_info_level <= DINFO_LEVEL_TERSE)
+ variable declarations or definitions except for public ones. */
+ if (debug_info_level < DINFO_LEVEL_TERSE
+ || (debug_info_level == DINFO_LEVEL_TERSE
+ && !TREE_PUBLIC(decl_or_origin)))
break;
/* Avoid generating stray type DIEs during late dwarf dumping.
@@ -26831,8 +26833,10 @@ dwarf2out_decl (tree decl)
context_die = lookup_decl_die (DECL_CONTEXT (decl));
/* If we are in terse mode, don't generate any DIEs to represent any
- variable declarations or definitions. */
- if (debug_info_level <= DINFO_LEVEL_TERSE)
+ variable declarations or definitions except public ones. */
+ if (debug_info_level < DINFO_LEVEL_TERSE
+ || (debug_info_level == DINFO_LEVEL_TERSE
+ && !TREE_PUBLIC(decl)))
return;
break;
--
2.20.1
