From: Mark Dickinson <dickinsm@gmail.com>
Date: Sat, 18 Apr 2009 10:16:35 +0000 (+0000)
Subject: Issue #5781: Only use legacy string<->double conversions when
X-Git-Tag: v3.1b1~254
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=60fd0999cce17ec8603edf4219f686c37a260d7b;p=python

Issue #5781: Only use legacy string<->double conversions when
we can't figure out how to get and set the x87 control word.
---

diff --git a/Include/pyport.h b/Include/pyport.h
index ed435697d3..9b8b1e7f82 100644
--- a/Include/pyport.h
+++ b/Include/pyport.h
@@ -506,8 +506,10 @@ extern "C" {
 #define PY_NO_SHORT_FLOAT_REPR
 #endif
 
-/* double rounding is symptomatic of use of extended precision on x86 */
-#ifdef X87_DOUBLE_ROUNDING
+/* double rounding is symptomatic of use of extended precision on x86.  If
+   we're seeing double rounding, and we don't have any mechanism available for
+   changing the FPU rounding precision, then don't use Python/dtoa.c. */
+#if defined(X87_DOUBLE_ROUNDING) && !defined(HAVE_GCC_ASM_FOR_X87)
 #define PY_NO_SHORT_FLOAT_REPR
 #endif