Rework the way we try to check for libm overflow, given that C99 no longer

requires that errno ever get set, and it looks like glibc is already
playing that game.  New rules:

+ Never use HUGE_VAL.  Use the new Py_HUGE_VAL instead.

+ Never believe errno.  If overflow is the only thing you're interested in,
  use the new Py_OVERFLOWED(x) macro.  If you're interested in any libm
  errors, use the new Py_SET_ERANGE_IF_OVERFLOW(x) macro, which attempts
  to set errno the way C89 said it worked.

Unfortunately, none of these are reliable, but they work on Windows and I
*expect* under glibc too.

1 files changed, 2 insertions, 15 deletions

diff --git a/Modules/cmathmodule.c b/Modules/cmathmodule.c
index 2cef27c..34b0ce8 100644
--- a/Modules/cmathmodule.c
+++ b/Modules/cmathmodule.c
@@ -4,19 +4,6 @@
 
 #include "Python.h"
 
-#ifdef i860
-/* Cray APP has bogus definition of HUGE_VAL in <math.h> */
-#undef HUGE_VAL
-#endif
-
-#ifdef HUGE_VAL
-#define CHECK(x) if (errno != 0) ; \
-	else if (-HUGE_VAL <= (x) && (x) <= HUGE_VAL) ; \
-	else errno = ERANGE
-#else
-#define CHECK(x) /* Don't know how to check */
-#endif
-
 #ifndef M_PI
 #define M_PI (3.141592653589793239)
 #endif
@@ -366,8 +353,8 @@ math_1(PyObject *args, Py_complex (*func)(Py_complex))
 	PyFPE_START_PROTECT("complex function", return 0)
 	x = (*func)(x);
 	PyFPE_END_PROTECT(x)
-	CHECK(x.real);
-	CHECK(x.imag);
+	Py_SET_ERANGE_IF_OVERFLOW(x.real);
+	Py_SET_ERANGE_IF_OVERFLOW(x.imag);
 	if (errno != 0)
 		return math_error();
 	else