Merge pull request #555 from cffk/c99-math-test

Add tests for C99 math functions, hypot, atanh, cbrt, etc.

-DHAVE_C99_MATH=1 is provided if these functions are available.  This
will be used by the next release of geodesic.c.

CMakeLists.txt

@@ -65,6 +65,28 @@ if (HAVE_PTHREAD_MUTEX_RECURSIVE_DEFN)
     add_definitions(-DHAVE_PTHREAD_MUTEX_RECURSIVE=1)
 endif()
 
+include (CheckCSourceCompiles)
+if (MSVC)
+  set (CMAKE_REQUIRED_FLAGS "${CMAKE_C_FLAGS} /WX")
+else ()
+  set (CMAKE_REQUIRED_LIBRARIES m)
+  set (CMAKE_REQUIRED_FLAGS "${CMAKE_C_FLAGS} -Werror")
+endif ()
+# Check whether the C99 math function: hypot, atanh, etc. are available.
+check_c_source_compiles (
+  "#include <math.h>
+int main() {
+  int q;
+  return (int)(hypot(3.0, 4.0) + atanh(0.8) + cbrt(8.0) +
+               remquo(100.0, 90.0, &q) +
+               remainder(100.0, 90.0) + copysigna(1.0, -0.0));
+}\n" C99_MATH)
+if (C99_MATH)
+  add_definitions (-DHAVE_C99_MATH=1)
+else ()
+  add_definitions (-DHAVE_C99_MATH=0)
+endif ()
+
 boost_report_value(PROJ_PLATFORM_NAME)
 boost_report_value(PROJ_COMPILER_NAME)
 

configure.ac

@@ -29,6 +29,20 @@ CFLAGS="$save_CFLAGS"
 dnl We check for headers
 AC_HEADER_STDC
 
+dnl Check for C99 math functions
+save_CFLAGS="$CFLAGS"
+CFLAGS="$CFLAGS -Wall -Werror"
+AC_MSG_CHECKING([for C99 math functions])
+AC_LINK_IFELSE([AC_LANG_PROGRAM(
+        [#include <math.h>],
+        [int q;
+         return (int)(hypot(3.0, 4.0) + atanh(0.8) + cbrt(8.0) +
+                      remquo(100.0, 90.0, &q) +
+                      remainder(100.0, 90.0) + copysign(1.0, -0.0));])],
+        [AC_MSG_RESULT([yes]);C99_MATH="-DHAVE_C99_MATH=1"],
+        [AC_MSG_RESULT([no]);C99_MATH="-DHAVE_C99_MATH=0"])
+CFLAGS="$save_CFLAGS $C99_MATH"
+
 AC_CHECK_FUNC(localeconv, [AC_DEFINE(HAVE_LOCALECONV,1,[Define to 1 if you have localeconv])])
 
 dnl ---------------------------------------------------------------------------