--- /dev/null
+++ libgcc/config/rs6000/t-float128-freebsd
@@ -0,0 +1,22 @@
+# On FreeBSD there is no float128 IFUNC (rs6000/t-float128-hw needs the Linux
+# AT_PLATFORM auxv entry, absent on FreeBSD), so the software __float128/KFmode
+# helpers built by rs6000/t-float128 would only land in the static libgcc.a
+# (hidden) via LIB2ADD_ST.  Put them in the shared libgcc_s.so and export them
+# (see libgcc-freebsd-float128.ver) so gcc-built DSOs -- notably libstdc++.so,
+# which references e.g. __eqkf2 for IEEE-128 long double -- resolve them.
+#
+# Exclude __mulkc3/__divkc3: under -mabi=ieeelongdouble libgcc2.c's __multc3/
+# __divtc3 are already mangled to those names in libgcc_s.so, so adding rs6000's
+# own copies to the shared library would multiply-define them.  They stay
+# static-only; the .ver exports the libgcc2.c-provided ones.
+fp128_shared_src := $(filter-out %/_mulkc3.c %/_divkc3.c,$(fp128_src))
+LIB2ADD_ST := $(filter-out $(fp128_shared_src),$(LIB2ADD_ST))
+LIB2ADD += $(fp128_shared_src)
+SHLIB_MAPFILES += $(srcdir)/config/rs6000/libgcc-freebsd-float128.ver
+
+# clang emits the complex IEEE-128 helpers as __multc3/__divtc3 (TCmode) where
+# gcc names them __mulkc3/__divkc3 (KCmode).  Provide real TCmode forwarders
+# (freebsd-tc-alias.c) so clang-built DSOs that link gcc's libgcc_s -- e.g.
+# USES=fortran ports mixing clang C with gfortran -- resolve them.  Real symbols
+# survive mkmap-symver's map generation where a --defsym link alias would not.
+LIB2ADD += $(srcdir)/config/rs6000/freebsd-tc-alias.c