-mabi=ieeelongdouble triggers the stdc++ libraries _Float128
support, which then breaks if algorithm is included. For now,
explicitly disable _Float128 for such tests.
I have opened up GCC BZ 94080 to track this.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
$(foreach r,$(ldbl-128ibm-routines) $(ldbl-tests), \
$(objpfx)$(r)$(suf)): \
sysdep-CFLAGS := $(filter-out -mabi=ieeelongdouble,$(sysdep-CFLAGS))
+
+# TODO: a bug in stdc++ will fail if -mabi=ieeelongdouble and -mfloat128
+# are both enabled. The latter is enabled by default in GCC 8+. This is
+# tracked via GCC BZ 94080.
+ifeq ($(subdir),support)
+CFLAGS-links-dso-program.cc += -mno-float128
+endif
+ifeq ($(subdir),nptl)
+CFLAGS-tst-thread_local1.cc += -mno-float128
+CFLAGS-tst-minstack-throw.cc += -mno-float128
+endif