[gcc r11-8711] Fix build failure on Windows with older binutils

[Eric Botcazou <ebotcazou@gcc.gnu.org>]

https://gcc.gnu.org/g:d9d954ebd507572a460f93f404bba71e271e2dda

commit r11-8711-gd9d954ebd507572a460f93f404bba71e271e2dda
Author: Eric Botcazou <ebotcazou@adacore.com>
Date:   Fri Jul 9 12:08:52 2021 +0200

    Fix build failure on Windows with older binutils
    
    This is the build failure on Windows with binutils for which GNU as accepts
    the --gdwarf-5 switch but GNU ld generates broken binaries with DWARF 5.
    
    We already have the HAVE_LD_BROKEN_PE_DWARF5 kludge to disable DWARF 5 in
    this case but it only tames the DWARF version in the compiler, so the
    driver still passes --gdwarf-5 when invoked on an assembly file with -g.
    
    gcc/
            PR target/101377
            * gcc.c (ASM_DEBUG_DWARF_OPTION): Set again to --gdwarf2 in
            the case where HAVE_AS_WORKING_DWARF_N_FLAG is not defined
            and HAVE_LD_BROKEN_PE_DWARF5 is defined.

Diff:
---
 gcc/gcc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/gcc.c b/gcc/gcc.c
index 7837553958b..7c75d1314fa 100644
--- a/gcc/gcc.c
+++ b/gcc/gcc.c
@@ -910,7 +910,7 @@ proper position among the other output files.  */
    than in ASM_DEBUG_SPEC, so that it applies to both .s and .c etc.
    compilations.  */
 #  define ASM_DEBUG_DWARF_OPTION ""
-# elif defined(HAVE_AS_GDWARF_5_DEBUG_FLAG)
+# elif defined(HAVE_AS_GDWARF_5_DEBUG_FLAG) && !defined(HAVE_LD_BROKEN_PE_DWARF5)
 #  define ASM_DEBUG_DWARF_OPTION "%{%:dwarf-version-gt(4):--gdwarf-5;" \
 	"%:dwarf-version-gt(3):--gdwarf-4;"				\
 	"%:dwarf-version-gt(2):--gdwarf-3;"				\