test: Define optional exception classes

According to musl libc author:

"C99 requires the FE_ macros to be defined if and only if the exception they
correspond to is supported"

So we define these macros to 0 if they are not supported. Support for these FPU
exceptions is not necessary for correct functionality, but makes some tests less
effective.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=55771
Signed-off-by: Uli Schlachter <psychon@znc.in>

test/cairo-test.c

@@ -35,9 +35,6 @@
 #include <stdlib.h>
 #include <stdarg.h>
 #include <ctype.h>
-#if HAVE_FEENABLEEXCEPT
-#include <fenv.h>
-#endif
 #include <assert.h>
 #if HAVE_UNISTD_H
 #include <unistd.h>

test/cairo-test.h

@@ -62,6 +62,26 @@ typedef unsigned __int64 uint64_t;
 
 #endif
 
+#if HAVE_FENV_H
+# include <fenv.h>
+#endif
+/* The following are optional in C99, so define them if they aren't yet */
+#ifndef FE_DIVBYZERO
+#define FE_DIVBYZERO 0
+#endif
+#ifndef FE_INEXACT
+#define FE_INEXACT 0
+#endif
+#ifndef FE_INVALID
+#define FE_INVALID 0
+#endif
+#ifndef FE_OVERFLOW
+#define FE_OVERFLOW 0
+#endif
+#ifndef FE_UNDERFLOW
+#define FE_UNDERFLOW 0
+#endif
+
 #include <math.h>
 
 static inline double

test/invalid-matrix.c

@@ -33,10 +33,6 @@
 #define INFINITY HUGE_VAL
 #endif
 
-#if HAVE_FENV_H
-# include <fenv.h>
-#endif
-
 static cairo_test_status_t
 draw (cairo_t *cr, int width, int height)
 {