[06/11] Disable use of -fsignaling-nans if compiler does not support it

diff --git a/benchtests/Makefile b/benchtests/Makefile
index fc1cda7fc3..292976b26b 100644
--- a/benchtests/Makefile
+++ b/benchtests/Makefile
@@ -268,9 +268,9 @@  CFLAGS-bench-trunc.c += -fno-builtin
 CFLAGS-bench-truncf.c += -fno-builtin
 CFLAGS-bench-roundeven.c += -fno-builtin
 CFLAGS-bench-roundevenf.c += -fno-builtin
-CFLAGS-bench-isnan.c += -fsignaling-nans
-CFLAGS-bench-isinf.c += -fsignaling-nans
-CFLAGS-bench-isfinite.c += -fsignaling-nans
+CFLAGS-bench-isnan.c += $(config-cflags-signaling-nans)
+CFLAGS-bench-isinf.c += $(config-cflags-signaling-nans)
+CFLAGS-bench-isfinite.c += $(config-cflags-signaling-nans)
 
 ifeq (${BENCHSET},)
 bench-malloc := malloc-thread malloc-simple
diff --git a/configure b/configure
index 26bd8200dd..1f5916af3f 100755
--- a/configure
+++ b/configure
@@ -6396,6 +6396,28 @@  $as_echo "$libc_cv_cc_submachine" >&6; }
 fi
 
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for compiler option that -fsignaling-nans" >&5
+$as_echo_n "checking for compiler option that -fsignaling-nans... " >&6; }
+if ${libc_cv_cc_signaling_nans+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  if { ac_try='${CC-cc} -Werror -fsignaling-nans -xc /dev/null -S -o /dev/null'
+  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; }; then :
+  libc_cv_cc_signaling_nans=-fsignaling-nans
+else
+  libc_cv_cc_signaling_nans=
+fi
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_cc_signaling_nans" >&5
+$as_echo "$libc_cv_cc_signaling_nans" >&6; }
+config_vars="$config_vars
+config-cflags-signaling-nans = $libc_cv_cc_signaling_nans"
+
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking if $CC accepts -fno-tree-loop-distribute-patterns with \
 __attribute__ ((__optimize__))" >&5
 $as_echo_n "checking if $CC accepts -fno-tree-loop-distribute-patterns with \
diff --git a/configure.ac b/configure.ac
index a009e7a17f..c207503c8a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1487,6 +1487,16 @@  if test -n "$submachine"; then
 fi
 AC_SUBST(libc_cv_cc_submachine)
 
+dnl Determine if compiler supports -fsignaling-nans
+AC_CACHE_CHECK([for compiler option that -fsignaling-nans],
+	       libc_cv_cc_signaling_nans, [dnl
+LIBC_TRY_CC_OPTION([-Werror -fsignaling-nans],
+		   [libc_cv_cc_signaling_nans=-fsignaling-nans],
+		   [libc_cv_cc_signaling_nans=])
+])
+LIBC_CONFIG_VAR([config-cflags-signaling-nans],
+		[$libc_cv_cc_signaling_nans])
+
 AC_CACHE_CHECK(if $CC accepts -fno-tree-loop-distribute-patterns with \
 __attribute__ ((__optimize__)), libc_cv_cc_loop_to_function, [dnl
 cat > conftest.c <<EOF
diff --git a/math/Makefile b/math/Makefile
index 7dae2313ba..71708f5542 100644
--- a/math/Makefile
+++ b/math/Makefile
@@ -248,8 +248,11 @@  tests = test-matherr-3 test-fenv basic-test \
 	test-femode-traps test-iszero-excess-precision \
 	test-iseqsig-excess-precision test-flt-eval-method \
 	test-fp-ilogb-constants test-fp-llogb-constants \
-	test-fe-snans-always-signal test-narrow-macros \
+	test-narrow-macros \
 	test-nan-const $(tests-static)
+ifneq ($(config-cflags-signaling-nans),)
+tests += test-fe-snans-always-signal
+endif
 tests-static = test-fpucw-static test-fpucw-ieee-static \
 	       test-signgam-uchar-static test-signgam-uchar-init-static \
 	       test-signgam-uint-static test-signgam-uint-init-static \
@@ -421,7 +424,7 @@  CFLAGS-test-float-vlen16-wrappers.c += $(float-vlen16-arch-ext-cflags)
 # exceptions.  Thus both versions of the classification macros are
 # validated.
 libm-test-no-inline-cflags = -fno-inline -ffloat-store -fno-builtin \
-			     -fsignaling-nans
+			     $(config-cflags-signaling-nans)
 CFLAGS-test-tgmath.c += -fno-builtin
 # The following testcase uses very long lines (>3 million), so it may take a
 # while to compile it. See: http://llvm.org/bugs/show_bug.cgi?id=14106 and
@@ -430,7 +433,7 @@  CFLAGS-test-tgmath2.c += -fno-builtin
 CFLAGS-test-tgmath-ret.c += -fno-builtin
 CFLAGS-test-powl.c += -fno-builtin
 
-CFLAGS-test-snan.c += -fsignaling-nans
+CFLAGS-test-snan.c += $(config-cflags-signaling-nans)
 
 CFLAGS-test-signgam-uchar.c += -std=c99
 CFLAGS-test-signgam-uchar-init.c += -std=c99
@@ -456,7 +459,7 @@  CFLAGS-test-iszero-excess-precision.c += -fexcess-precision=standard
 CFLAGS-test-iseqsig-excess-precision.c += -fexcess-precision=standard
 CFLAGS-test-flt-eval-method.c += -fexcess-precision=standard
 
-CFLAGS-test-fe-snans-always-signal.c += -fsignaling-nans
+CFLAGS-test-fe-snans-always-signal.c += $(config-cflags-signaling-nans)
 
 CFLAGS-test-nan-const.c += -fno-builtin
 
@@ -768,10 +771,10 @@  endif
 
 # These files quiet sNaNs in a way that is optimized away without
 # -fsignaling-nans.
-CFLAGS-s_modf.c += -fsignaling-nans
-CFLAGS-s_modff.c += -fsignaling-nans
-CFLAGS-s_modfl.c += -fsignaling-nans
-CFLAGS-s_modff128.c += -fsignaling-nans
+CFLAGS-s_modf.c += $(config-cflags-signaling-nans)
+CFLAGS-s_modff.c += $(config-cflags-signaling-nans)
+CFLAGS-s_modfl.c += $(config-cflags-signaling-nans)
+CFLAGS-s_modff128.c += $(config-cflags-signaling-nans)
 
 $(addprefix $(objpfx),\
 	    $(filter-out $(tests-static) $(libm-tests-vector),\
diff --git a/math/libm-test-fpclassify.inc b/math/libm-test-fpclassify.inc
index f805ad5e23..dafb1fc6bf 100644
--- a/math/libm-test-fpclassify.inc
+++ b/math/libm-test-fpclassify.inc
@@ -22,8 +22,10 @@  static const struct test_f_i_data fpclassify_test_data[] =
   {
     TEST_f_i (fpclassify, qnan_value, FP_NAN, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_i (fpclassify, -qnan_value, FP_NAN, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#ifdef __SUPPORT_SNAN__
     TEST_f_i (fpclassify, snan_value, FP_NAN, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_i (fpclassify, -snan_value, FP_NAN, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#endif
     TEST_f_i (fpclassify, plus_infty, FP_INFINITE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_i (fpclassify, minus_infty, FP_INFINITE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_i (fpclassify, plus_zero, FP_ZERO, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
diff --git a/math/libm-test-isfinite.inc b/math/libm-test-isfinite.inc
index 37a4ca4298..5b22dbce9f 100644
--- a/math/libm-test-isfinite.inc
+++ b/math/libm-test-isfinite.inc
@@ -33,8 +33,10 @@  static const struct test_f_i_data isfinite_test_data[] =
     TEST_f_b (isfinite, minus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isfinite, qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isfinite, -qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#ifdef __SUPPORT_SNAN__
     TEST_f_b (isfinite, snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isfinite, -snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#endif
   };
 
 static void
diff --git a/math/libm-test-isinf.inc b/math/libm-test-isinf.inc
index 26548729e9..990babf01c 100644
--- a/math/libm-test-isinf.inc
+++ b/math/libm-test-isinf.inc
@@ -33,8 +33,10 @@  static const struct test_f_i_data isinf_test_data[] =
     TEST_f_b (isinf, minus_infty, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isinf, qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isinf, -qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#ifdef __SUPPORT_SNAN__
     TEST_f_b (isinf, snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isinf, -snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#endif
   };
 
 #if TEST_COND_intel96
diff --git a/math/libm-test-isnan.inc b/math/libm-test-isnan.inc
index 026b61c216..2edfd7c62d 100644
--- a/math/libm-test-isnan.inc
+++ b/math/libm-test-isnan.inc
@@ -33,8 +33,10 @@  static const struct test_f_i_data isnan_test_data[] =
     TEST_f_b (isnan, minus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isnan, qnan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isnan, -qnan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#ifdef __SUPPORT_SNAN__
     TEST_f_b (isnan, snan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isnan, -snan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#endif
   };
 
 #if TEST_COND_intel96
diff --git a/math/libm-test-isnormal.inc b/math/libm-test-isnormal.inc
index e1e8a3b270..e4f6a8f74c 100644
--- a/math/libm-test-isnormal.inc
+++ b/math/libm-test-isnormal.inc
@@ -33,8 +33,10 @@  static const struct test_f_i_data isnormal_test_data[] =
     TEST_f_b (isnormal, minus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isnormal, qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isnormal, -qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#ifdef __SUPPORT_SNAN__
     TEST_f_b (isnormal, snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isnormal, -snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#endif
   };
 
 static void
diff --git a/math/libm-test-issubnormal.inc b/math/libm-test-issubnormal.inc
index 38564f2bcc..cc045435ad 100644
--- a/math/libm-test-issubnormal.inc
+++ b/math/libm-test-issubnormal.inc
@@ -33,8 +33,10 @@  static const struct test_f_i_data issubnormal_test_data[] =
     TEST_f_b (issubnormal, minus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (issubnormal, qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (issubnormal, -qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#ifdef __SUPPORT_SNAN__
     TEST_f_b (issubnormal, snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (issubnormal, -snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#endif
   };
 
 static void
diff --git a/math/libm-test-iszero.inc b/math/libm-test-iszero.inc
index cfd3d1fecb..e56eac4e76 100644
--- a/math/libm-test-iszero.inc
+++ b/math/libm-test-iszero.inc
@@ -33,8 +33,10 @@  static const struct test_f_i_data iszero_test_data[] =
     TEST_f_b (iszero, minus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (iszero, qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (iszero, -qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#ifdef __SUPPORT_SNAN__
     TEST_f_b (iszero, snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (iszero, -snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#endif
   };
 
 static void
diff --git a/math/test-snan.c b/math/test-snan.c
index 4d7bd54ade..fadde89764 100644
--- a/math/test-snan.c
+++ b/math/test-snan.c
@@ -25,8 +25,10 @@ 
 #include <setjmp.h>
 
 #include <math-tests.h>
+#include <support/check.h>
 
 
+#ifdef __SUPPORT_SNAN__
 static sigjmp_buf sigfpe_buf;
 
 static void
@@ -123,10 +125,12 @@  NAME (void)								      \
 TEST_FUNC (float_test, float, f)
 TEST_FUNC (double_test, double, )
 TEST_FUNC (ldouble_test, long double, l)
+#endif
 
 static int
 do_test (void)
 {
+#ifdef __SUPPORT_SNAN__
   signal (SIGFPE, &myFPsighandler);
 
   float_test ();
@@ -134,7 +138,9 @@  do_test (void)
   ldouble_test ();
 
   return errors != 0;
+#else
+  FAIL_UNSUPPORTED ("compiler does not support -fsignaling-nans");
+#endif
 }
 
-#define TEST_FUNCTION do_test ()
-#include "../test-skeleton.c"
+#include <support/test-driver.c>
diff --git a/sysdeps/powerpc/nofpu/Makefile b/sysdeps/powerpc/nofpu/Makefile
index 3b51ff6d18..fa462339ba 100644
--- a/sysdeps/powerpc/nofpu/Makefile
+++ b/sysdeps/powerpc/nofpu/Makefile
@@ -27,18 +27,18 @@  CPPFLAGS += -I../soft-fp/
 CFLAGS-e_atan2l.c += -fno-builtin-fabsl
 CFLAGS-e_hypotl.c += -fno-builtin-fabsl
 CFLAGS-e_powl.c += -fno-builtin-fabsl
-CFLAGS-s_cacosl.c += -fsignaling-nans
-CFLAGS-s_cacoshl.c += -fsignaling-nans
-CFLAGS-s_casinhl.c += -fsignaling-nans
-CFLAGS-s_catanl.c += -fsignaling-nans
-CFLAGS-s_catanhl.c += -fsignaling-nans
-CFLAGS-s_ccoshl.c += -fno-builtin-fabsl -fsignaling-nans
-CFLAGS-s_cexpl.c += -fsignaling-nans
-CFLAGS-s_csinhl.c += -fno-builtin-fabsl -fsignaling-nans
-CFLAGS-s_clogl.c += -fno-builtin-fabsl -fsignaling-nans
-CFLAGS-s_clog10l.c += -fno-builtin-fabsl -fsignaling-nans
-CFLAGS-s_csinl.c += -fno-builtin-fabsl -fsignaling-nans
-CFLAGS-s_csqrtl.c += -fno-builtin-fabsl -fsignaling-nans
+CFLAGS-s_cacosl.c += $(config-cflags-signaling-nans)
+CFLAGS-s_cacoshl.c += $(config-cflags-signaling-nans)
+CFLAGS-s_casinhl.c += $(config-cflags-signaling-nans)
+CFLAGS-s_catanl.c += $(config-cflags-signaling-nans)
+CFLAGS-s_catanhl.c += $(config-cflags-signaling-nans)
+CFLAGS-s_ccoshl.c += -fno-builtin-fabsl $(config-cflags-signaling-nans)
+CFLAGS-s_cexpl.c += $(config-cflags-signaling-nans)
+CFLAGS-s_csinhl.c += -fno-builtin-fabsl $(config-cflags-signaling-nans)
+CFLAGS-s_clogl.c += -fno-builtin-fabsl $(config-cflags-signaling-nans)
+CFLAGS-s_clog10l.c += -fno-builtin-fabsl $(config-cflags-signaling-nans)
+CFLAGS-s_csinl.c += -fno-builtin-fabsl $(config-cflags-signaling-nans)
+CFLAGS-s_csqrtl.c += -fno-builtin-fabsl $(config-cflags-signaling-nans)
 CFLAGS-w_acosl_compat.c += -fno-builtin-fabsl
 CFLAGS-w_asinl_compat.c += -fno-builtin-fabsl
 CFLAGS-w_atanhl_compat.c += -fno-builtin-fabsl
diff --git a/sysdeps/powerpc/powerpc32/power4/fpu/multiarch/Makefile b/sysdeps/powerpc/powerpc32/power4/fpu/multiarch/Makefile
index 1de0f9b350..64317506c6 100644
--- a/sysdeps/powerpc/powerpc32/power4/fpu/multiarch/Makefile
+++ b/sysdeps/powerpc/powerpc32/power4/fpu/multiarch/Makefile
@@ -37,6 +37,6 @@  CFLAGS-s_logbf-power7.c = -mcpu=power7
 
 # These files quiet sNaNs in a way that is optimized away without
 # -fsignaling-nans.
-CFLAGS-s_modf-ppc32.c += -fsignaling-nans
-CFLAGS-s_modff-ppc32.c += -fsignaling-nans
+CFLAGS-s_modf-ppc32.c += $(config-cflags-signaling-nans)
+CFLAGS-s_modff-ppc32.c += $(config-cflags-signaling-nans)
 endif
diff --git a/sysdeps/powerpc/powerpc64/be/fpu/multiarch/Makefile b/sysdeps/powerpc/powerpc64/be/fpu/multiarch/Makefile
index b27bad3ba4..36f4006059 100644
--- a/sysdeps/powerpc/powerpc64/be/fpu/multiarch/Makefile
+++ b/sysdeps/powerpc/powerpc64/be/fpu/multiarch/Makefile
@@ -62,6 +62,6 @@  CFLAGS-s_logb-power7.c = -mcpu=power7
 
 # These files quiet sNaNs in a way that is optimized away without
 # -fsignaling-nans.
-CFLAGS-s_modf-ppc64.c += -fsignaling-nans
-CFLAGS-s_modff-ppc64.c += -fsignaling-nans
+CFLAGS-s_modf-ppc64.c += $(config-cflags-signaling-nans)
+CFLAGS-s_modff-ppc64.c += $(config-cflags-signaling-nans)
 endif
diff --git a/sysdeps/powerpc/powerpc64/le/fpu/multiarch/Makefile b/sysdeps/powerpc/powerpc64/le/fpu/multiarch/Makefile
index cc073b53d3..249850f410 100644
--- a/sysdeps/powerpc/powerpc64/le/fpu/multiarch/Makefile
+++ b/sysdeps/powerpc/powerpc64/le/fpu/multiarch/Makefile
@@ -130,8 +130,8 @@  generated += $(f128-march-routines)
 CFLAGS-float128-ifunc.c += $(type-float128-CFLAGS) $(no-gnu-attribute-CFLAGS)
 
 # Copy special CFLAGS for some functions
-CFLAGS-s_modff128-power9.c += -fsignaling-nans
-CFLAGS-m_modff128-power9.c += -fsignaling-nans
+CFLAGS-s_modff128-power9.c += $(config-cflags-signaling-nans)
+CFLAGS-m_modff128-power9.c += $(config-cflags-signaling-nans)
 
 # Generate ifunc wrapper files and target specific wrappers around
 # each routine above.  Note, m_%.c files are fixed up to include