https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92680
--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> --- It looks like the problem is fixed in ./mpfr-4.1.0/: AC_DEFUN([MPFR_C_REALFP_FORMAT], [AC_REQUIRE([AC_PROG_CC]) AC_REQUIRE([AC_PROG_AWK]) AC_REQUIRE([AC_OBJEXT]) AS_VAR_PUSHDEF([my_Type_var], [mpfr_cv_c_$1_format])dnl AC_CACHE_CHECK([format of floating-point type `$1'], my_Type_var, [my_Type_var=unknown cat >conftest.c <<\EOF [ #include <stdio.h> /* "before" is 16 bytes to ensure there's no padding between it and "x". We're not expecting any type bigger than 16 bytes or with alignment requirements stricter than 16 bytes. */ typedef struct { char before[16]; $1 x; char after[8]; } foo_t; foo_t foo = { { '\0', '\0', '\0', '\0', '\0', '\0', '\0', '\0', '\001', '\043', '\105', '\147', '\211', '\253', '\315', '\357' }, -123456789.0, { '\376', '\334', '\272', '\230', '\166', '\124', '\062', '\020' } }; int main (void) { int i; for (i = 0; i < 8; i++) printf ("%d %$2f\n", foo.before[i] + foo.after[i], foo.x); return 0; } ] EOF mpfr_compile="$CC $CFLAGS $CPPFLAGS $LDFLAGS conftest.c -o conftest$EXEEXT >&AS_MESSAGE_LOG_FD 2>&1" if AC_TRY_EVAL(mpfr_compile); then cat >conftest.awk <<\EOF [ BEGIN { found = 0 } ....