Undefine redirections after long double definition on __LDBL_COMPAT [BZ #23294]

After defining the long double redirections to double, __MATHDECL_1 has
to be redefined to its previous state in order to avoid redirecting all
subsequent types.

2 files changed, 90 insertions, 1 deletions

diff --git a/sysdeps/ieee754/ldbl-opt/Makefile b/sysdeps/ieee754/ldbl-opt/Makefile
index 791a5eabd2..4e41a27e80 100644
--- a/sysdeps/ieee754/ldbl-opt/Makefile
+++ b/sysdeps/ieee754/ldbl-opt/Makefile
@@ -172,9 +172,11 @@ CFLAGS-nldbl-y0.c = -fno-builtin-y0l
 CFLAGS-nldbl-y1.c = -fno-builtin-y1l
 CFLAGS-nldbl-yn.c = -fno-builtin-ynl
 
-tests += test-narrow-macros-ldbl-64 test-nldbl-redirect
+tests += test-narrow-macros-ldbl-64 test-nldbl-redirect \
+	 test-redirection-ldbl-64
 CFLAGS-test-narrow-macros-ldbl-64.c += -mlong-double-64
 CFLAGS-test-nldbl-redirect.c += -mlong-double-64
+CFLAGS-test-redirection-ldbl-64.c += -mlong-double-64
 
 $(objpfx)test-nldbl-redirect: $(objpfx)libnldbl_nonshared.a
 
diff --git a/sysdeps/ieee754/ldbl-opt/test-redirection-ldbl-64.c b/sysdeps/ieee754/ldbl-opt/test-redirection-ldbl-64.c
new file mode 100644
index 0000000000..cc683596a0
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-opt/test-redirection-ldbl-64.c
@@ -0,0 +1,87 @@
+/* Test if __LDBL_COMPAT redirections conflict with other types.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* Redirecting functions twice may lead to -Werror=pragmas errors.
+   In a __LDBL_COMPAT environment, only long double functions should be
+   redirected.  This test redirects math functions to a dummy function in
+   order to validate if they have not been redirected before.  */
+
+#include <math.h>
+#include <complex.h>
+
+#if defined __FINITE_MATH_ONLY__ && __FINITE_MATH_ONLY__ > 0
+# error "This test should never request finite functions"
+#endif
+
+#define MATH_REDIRX(function, to) \
+  extern typeof (function) function __asm__ ("" # to);
+#define MATH_REDIR(function) MATH_REDIRX (function, __ ## function)
+
+#if __HAVE_FLOAT32
+# define MATH_F32(function) MATH_REDIR(function ## f32)
+#else
+# define MATH_F32(function)
+#endif
+
+#if __HAVE_FLOAT32X
+# define MATH_F32X(function) MATH_REDIR(function ## f32x)
+#else
+# define MATH_F32X(function)
+#endif
+
+#if __HAVE_FLOAT64
+# define MATH_F64(function) MATH_REDIR(function ## f64)
+#else
+# define MATH_F64(function)
+#endif
+
+#if __HAVE_FLOAT64X
+# define MATH_F64X(function) MATH_REDIR(function ## f64x)
+#else
+# define MATH_F64X(function)
+#endif
+
+#define MATH_FUNCTION(function) \
+  MATH_REDIR(function); \
+  MATH_REDIR(function ## f); \
+  MATH_F32(function); \
+  MATH_F32X(function); \
+  MATH_F64(function); \
+  MATH_F64X(function);
+
+MATH_FUNCTION (acos);
+MATH_FUNCTION (asin);
+MATH_FUNCTION (exp);
+MATH_FUNCTION (floor);
+MATH_FUNCTION (ldexp);
+MATH_FUNCTION (log);
+MATH_FUNCTION (sin);
+MATH_FUNCTION (cabs);
+MATH_FUNCTION (cacos);
+MATH_FUNCTION (casin);
+MATH_FUNCTION (clog);
+MATH_FUNCTION (csin);
+
+static int
+do_test (void)
+{
+  /* This is a compilation test.  */
+  return 0;
+}
+
+#include <support/test-driver.c>