configure: don't bother to run checks which can be done at the compile time.

[ginac.git] / ginac / utils.h

diff --git a/ginac/utils.h b/ginac/utils.h
index eaa9a723ac0a6d5db1533954976f5958a19bbabc..3c293ea8c5e2e3f7b42391e701f780d3e064acdd 100644 (file)
--- a/ginac/utils.h
+++ b/ginac/utils.h
@@ -81,24 +81,26 @@ inline unsigned golden_ratio_hash(p_int n)
 {
        // This function works much better when fast arithmetic with at
        // least 64 significant bits is available.
-#if SIZEOF_LONG >= 8
+       if (sizeof(long) >= 8) {
        // So 'long' has 64 bits.  Excellent!  We prefer it because it might be
        // more efficient than 'long long'.
        unsigned long l = n * 0x4f1bbcddUL;
        return (unsigned)l;
-#elif SIZEOF_LONG_LONG >= 8
+       }
+#ifdef HAVE_LONG_LONG
+       else if (sizeof(long long) >= 8) {
        // This requires 'long long' (or an equivalent 64 bit type)---which is,
        // unfortunately, not ANSI-C++-compliant.
        // (Yet C99 demands it, which is reason for hope.)
        unsigned long long l = n * 0x4f1bbcddULL;
        return (unsigned)l;
-#else
+       }
+#endif
        // Without a type with 64 significant bits do the multiplication manually
        // by splitting n up into the lower and upper two bytes.
        const unsigned n0 = (n & 0x0000ffffU);
        const unsigned n1 = (n & 0xffff0000U) >> 16;
        return (n0 * 0x0000bcddU) + ((n1 * 0x0000bcddU + n0 * 0x00004f1bU) << 16);
-#endif
 }
 
 /* Compute the sign of a permutation of a container, with and without an