Enable fp-exceptions

[alexxy/gromacs.git] / src / gromacs / math / utilities.c

diff --git a/src/gromacs/math/utilities.c b/src/gromacs/math/utilities.c
index 03b7134427da15d9a9509925dacebdf899ed1c9a..25f24b5beb913c33f738adad63857cdd8f30ff3b 100644 (file)
--- a/src/gromacs/math/utilities.c
+++ b/src/gromacs/math/utilities.c
@@ -47,6 +47,9 @@
 #ifdef HAVE__FINITE
 #include <float.h>
 #endif
+#ifndef GMX_NATIVE_WINDOWS
+#include <fenv.h>
+#endif
 
 int gmx_nint(real a)
 {
@@ -851,3 +854,35 @@ int gmx_greatest_common_divisor(int p, int q)
     }
     return p;
 }
+
+int gmx_feenableexcept()
+{
+#ifdef HAVE_FEENABLEEXCEPT
+    return feenableexcept(FE_DIVBYZERO | FE_INVALID | FE_OVERFLOW);
+#elif (defined(__i386__) || defined(__x86_64__)) && defined(__APPLE__)
+    /* Author:  David N. Williams
+     * License:  Public Domain
+     *
+     * Might also work on non-Apple Unix. But should be tested
+     * before enabling.
+     */
+    unsigned int  excepts = FE_DIVBYZERO | FE_INVALID | FE_OVERFLOW;
+    static fenv_t fenv;
+    unsigned int  new_excepts = excepts & FE_ALL_EXCEPT,
+                  old_excepts; // previous masks
+
+    if (fegetenv (&fenv) )
+    {
+        return -1;
+    }
+    old_excepts = fenv.__control & FE_ALL_EXCEPT;
+
+    // unmask
+    fenv.__control &= ~new_excepts;
+    fenv.__mxcsr   &= ~(new_excepts << 7);
+
+    return ( fesetenv (&fenv) ? -1 : old_excepts );
+#else
+    return -1;
+#endif
+}