build: Only use gas_flag/gnu_ld_flag internally [PR123841]

gcc/acinclude.m4, gcc/config.gcc, and gcc/configure.ac have two
different variables that are checked to determine if GNU as and/or GNU
ld are used.  config.gcc describes them like this:

  gas_flag		Either yes or no depending on whether GNU as was
			requested.
  gnu_ld_flag		Either yes or no depending on whether GNU ld was
			requested.

  gas			Set to yes or no depending on whether the target
			system normally uses GNU as.
  gnu_ld		Set to yes or no depending on whether the target
			system normally uses GNU ld.

I find this duplication highly confusing: what's the point of what a
target normally uses when it can just be determined at configure time if
the assembler/linker used is gas/gnu_ld?

There are two uses for those variables:

* gas/gnu_ld determine the setting of HAVE_GNU_AS/HAVE_GNU_LD.  In this
  case only, the normally part may be good enough, so this patch doesn't
  touch it.

* However, there are several other places where this isn't good enough:
  when the assembler/linker is invoked at configure time, it's crucial
  that the right options and input syntax are use for the tool in
  question.

Therefore this patch determines gas_flag/gnu_ld_flag at configure time
if they are not yet set otherwise.  All tests that need to know which
tool is used now check gas_flag/gnu_ld_flag only.

Tested on {i386,amd64}-pc-solaris2.11, {i686,x86_64}-pc-linux-gnu,
{i386,x86_64}-apple-darwin, and sparc64-unknown-linux-gnu.

2026-01-30  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

	gcc:
	PR other/123841
	* acinclude.m4 (gcc_GAS_FLAGS): Check $gas_flag, $gnu_ld_flag
	instead of $gas, $gnu_ld.
	* configure.ac: Likewise.
	(gas_flag): Determine if not already set.
	(gnu_ld_flag): Likewise.
	(ld_32_opt): Only set after gnu_ld_flag is set.
	(ld_64_opt): Likewise.
	* configure: Regenerate.

0 files changed, 0 insertions, 0 deletions