https://lists.gnu.org/archive/html/libtool-patches/2024-01/msg00029.html
https://git.savannah.gnu.org/cgit/libtool.git/commit/?id=533d816dea307ad78c4e7ba16dcdec4c285b0bc8

From 50f97756e75da06269374fff455cb211c7cf5cda Mon Sep 17 00:00:00 2001
From: Sam James <sam@gentoo.org>
Date: Sun, 14 Jan 2024 06:27:33 +0000
Subject: ltmain.in: Pass through -fdiagnostics-color, -frecord-gcc-switches

* -fdiagnostics-color: who doesn't like color? No reason to strip it. This
  makes the link phase stick out like a sore thumb if there's warnings emitted.

* -frecord-gcc-switches: we use it in Gentoo to check if a package respects
  *FLAGS. Note that we do not need to include -grecord-gcc-switches explicitly
  here as -g* is already whitelisted.

* build-aux/ltmain.in: Handle -fdiagnostics-color* & -frecord-gcc-switches.

[rebased on top of Debian ltmain.sh]
Signed-off-by: Eli Schwartz <eschwartz93@gmail.com>
--- ltmain.in
+++ ltmain.in
@@ -7559,6 +7559,8 @@ func_mode_link ()
       # -O*, -g*, -flto*, -fwhopr*, -fuse-linker-plugin GCC link-time optimization
       # -specs=*             GCC specs files
       # -stdlib=*            select c++ std lib with clang
+      # -fdiagnostics-color* simply affects output
+      # -frecord-gcc-switches used to verify flags were respected
       # -fsanitize=*         Clang/GCC memory and address sanitizer
       # -fuse-ld=*           Linker select flags for GCC
       # -static-*            direct GCC to link specific libraries statically
@@ -7568,6 +7570,7 @@ func_mode_link ()
       -64|-mips[0-9]|-r[0-9][0-9]*|-xarch=*|-xtarget=*|+DA*|+DD*|-q*|-m*| \
       -t[45]*|-txscale*|-p|-pg|--coverage|-fprofile-*|-F*|@*|-tp=*|--sysroot=*| \
       -O*|-g*|-flto*|-fwhopr*|-fuse-linker-plugin|-fstack-protector*|-stdlib=*| \
+      -fdiagnostics-color*|-frecord-gcc-switches| \
       -specs=*|-fsanitize=*|-fuse-ld=*|-static-*|-fcilkplus|-Wa,*|-Werror|-Werror=*)
         func_quote_arg pretty "$arg"
 	arg=$func_quote_arg_result
--
2.43.0