Add support for Solaris 2.6 on sun4m builds

It is an excellent platform for catching bugs: big-endian, slow enough
that a context switch in the middle of an operation becomes a regular
occurrence, and all that on a SMP box.  Or: I just wanted to see if it
would work.

Signed-off-by: Erik Boasson <eb@ilities.com>

ports/solaris2.6/include/math.h

@@ -0,0 +1,22 @@
+#ifndef DDSRT_FIXUP_MATH_H
+#define DDSRT_FIXUP_MATH_H
+
+#include_next "math.h"
+
+/* INFINITY, HUGE_VALF, HUGE_VALL are all standard C99, but Solaris 2.6
+   antedates that by a good margin and GCC's fixed-up headers don't
+   define it, so we do it here */
+#undef HUGE_VAL
+#ifdef __GNUC__
+#  define INFINITY (__builtin_inff ())
+#  define HUGE_VAL (__builtin_huge_val ())
+#  define HUGE_VALF (__builtin_huge_valf ())
+#  define HUGE_VALL (__builtin_huge_vall ())
+#else
+#  define INFINITY 1e10000
+#  define HUGE_VAL 1e10000
+#  define HUGE_VALF 1e10000f
+#  define HUGE_VALL 1e10000L
+#endif
+
+#endif /* DDSRT_FIXUP_MATH_H */