Since the switch to -std=gnu23 by default, float.h (included from
tsystem.h) defines INFINITY macro (to __builtin_inff ()), which now
results in a warning when compiling libgcc2.c which defines it
to something else (and, worse aarch64 compiles it with -Werror and
build fails).
libgcc2.c asserts INFINITY has the expected type which depends on
the macros with which libgcc2.c is being compiled, so guarding
the define with #ifndef INFINITY wouldn't work.
So this patch instead #undefs the macro before defining it.
2024-11-16 Jakub Jelinek <jakub@redhat.com>
PR libgcc/117624
* libgcc2.c (INFINITY): Add #undef before #define.
#define isfinite(x) __builtin_isfinite (x)
#define isinf(x) __builtin_isinf (x)
+#undef INFINITY
#define INFINITY CONCAT2(__builtin_huge_val, CEXT) ()
#define I 1i