# HG changeset patch
# User Bruno Haible <bruno@clisp.org>
# Date 1318324404 -7200
# Node ID cfc88a2774f7d30e508843f7cd300f83e37d89bd
# Parent  83c276c24d2a3f57eb8600cd9a3a751254e35d92
asinl: Simplify for platforms where 'long double' == 'double'.

* lib/asinl.c (asinl) [HAVE_SAME_LONG_DOUBLE_AS_DOUBLE]: New
alternative implementation.
* m4/asinl.m4 (gl_FUNC_ASINL): Require gl_LONG_DOUBLE_VS_DOUBLE.
Determine ASINL_LIBM according to HAVE_SAME_LONG_DOUBLE_AS_DOUBLE.
* modules/asinl (Depends-on): Add asin. Update conditions.

diff --git a/ChangeLog b/ChangeLog
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2011-10-10  Bruno Haible  <bruno@clisp.org>
+
+	asinl: Simplify for platforms where 'long double' == 'double'.
+	* lib/asinl.c (asinl) [HAVE_SAME_LONG_DOUBLE_AS_DOUBLE]: New
+	alternative implementation.
+	* m4/asinl.m4 (gl_FUNC_ASINL): Require gl_LONG_DOUBLE_VS_DOUBLE.
+	Determine ASINL_LIBM according to HAVE_SAME_LONG_DOUBLE_AS_DOUBLE.
+	* modules/asinl (Depends-on): Add asin. Update conditions.
+
 2011-10-10  Bruno Haible  <bruno@clisp.org>
 
 	tanl: Simplify for platforms where 'long double' == 'double'.
diff --git a/lib/asinl.c b/lib/asinl.c
--- a/lib/asinl.c
+++ b/lib/asinl.c
@@ -14,6 +14,16 @@
 /* Specification.  */
 #include <math.h>
 
+#if HAVE_SAME_LONG_DOUBLE_AS_DOUBLE
+
+long double
+asinl (long double x)
+{
+  return asin (x);
+}
+
+#else
+
 /*
   Long double expansions contributed by
   Stephen L. Moshier <moshier@na-net.ornl.gov>
@@ -188,6 +198,8 @@
   return t * sign;
 }
 
+#endif
+
 #if 0
 int
 main (void)
diff --git a/m4/asinl.m4 b/m4/asinl.m4
--- a/m4/asinl.m4
+++ b/m4/asinl.m4
@@ -1,4 +1,4 @@
-# asinl.m4 serial 5
+# asinl.m4 serial 6
 dnl Copyright (C) 2010-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -7,6 +7,8 @@
 AC_DEFUN([gl_FUNC_ASINL],
 [
   AC_REQUIRE([gl_MATH_H_DEFAULTS])
+  AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
+
   dnl Persuade glibc <math.h> to declare asinl().
   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
 
@@ -56,12 +58,17 @@
     HAVE_DECL_ASINL=0
     HAVE_ASINL=0
     dnl Find libraries needed to link lib/asinl.c.
-    AC_REQUIRE([gl_FUNC_SQRTL])
-    dnl Append $SQRTL_LIBM to ASINL_LIBM, avoiding gratuitous duplicates.
-    case " $ASINL_LIBM " in
-      *" $SQRTL_LIBM "*) ;;
-      *) ASINL_LIBM="$ASINL_LIBM $SQRTL_LIBM" ;;
-    esac
+    if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
+      AC_REQUIRE([gl_FUNC_ASIN])
+      ASINL_LIBM="$ASIN_LIBM"
+    else
+      AC_REQUIRE([gl_FUNC_SQRTL])
+      dnl Append $SQRTL_LIBM to ASINL_LIBM, avoiding gratuitous duplicates.
+      case " $ASINL_LIBM " in
+        *" $SQRTL_LIBM "*) ;;
+        *) ASINL_LIBM="$ASINL_LIBM $SQRTL_LIBM" ;;
+      esac
+    fi
   fi
   AC_SUBST([ASINL_LIBM])
 ])
diff --git a/modules/asinl b/modules/asinl
--- a/modules/asinl
+++ b/modules/asinl
@@ -8,7 +8,8 @@
 Depends-on:
 math
 extensions
-sqrtl           [test $HAVE_ASINL = 0]
+asin            [test $HAVE_ASINL = 0 && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1]
+sqrtl           [test $HAVE_ASINL = 0 && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 0]
 
 configure.ac:
 gl_FUNC_ASINL