1 files changed, 38 insertions, 0 deletions
diff --git a/lib/isnand-nolibm.h b/lib/isnand-nolibm.h
new file mode 100644
index 0000000..bb5a38b
--- /dev/null
+++ b/lib/isnand-nolibm.h
@@ -0,0 +1,38 @@
+/* Test for NaN that does not need libm.
+   Copyright (C) 2007-2023 Free Software Foundation, Inc.
+
+   This file 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.
+
+   This file 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 this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+/* This file uses HAVE_ISNAND_IN_LIBC.  */
+#if !_GL_CONFIG_H_INCLUDED
+ #error "Please include config.h first."
+#endif
+
+#if HAVE_ISNAND_IN_LIBC
+/* Get declaration of isnan macro.  */
+# include <math.h>
+# if (__GNUC__ >= 4) || (__clang_major__ >= 4)
+   /* GCC >= 4.0 and clang provide a type-generic built-in for isnan.  */
+#  undef isnand
+#  define isnand(x) __builtin_isnan ((double)(x))
+# else
+#  undef isnand
+#  define isnand(x) isnan ((double)(x))
+# endif
+#else
+/* Test whether X is a NaN.  */
+# undef isnand
+# define isnand rpl_isnand
+extern int isnand (double x);
+#endif