This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Do not declare _Float128 support for powerpc64le -mlong-double-64 (bug 22402) [committed]
- From: Joseph Myers <joseph at codesourcery dot com>
- To: <libc-alpha at sourceware dot org>
- Date: Mon, 6 Nov 2017 13:26:55 +0000
- Subject: Do not declare _Float128 support for powerpc64le -mlong-double-64 (bug 22402) [committed]
- Authentication-results: sourceware.org; auth=none
The powerpc bits/floatn.h declares _Float128 support to be present
when the compiler supports it for powerpc64le. However, in the case
where -mlong-double-64 is used, __MATH_TG does not actually support
_Float128; it only supports _Float128 in the distinct-long-double
case.
This shows up as a build failure when building glibc mainline with GCC
mainline, given the recently added sanity check in math.h for
configurations supported by __MATH_TG, as the compat code for
-mlong-double-64 fails to build. However, the bug was logically
present before that change (including in 2.26), just less visible.
This patch fixes the build failure by declaring _Float128 to be
unsupported in that case. (Of course this can't actually stop users
calling the type-generic macros with _Float128 arguments with
-mlong-double-64, just as they could be called with other unsupported
types on other platforms, but perhaps makes it less likely by making
all the type-specific _Float128 interfaces invisible in that case.)
Tested compilation for powerpc64le with build-many-glibcs.py. Committed.
2017-11-06 Joseph Myers <joseph@codesourcery.com>
[BZ #22402]
* sysdeps/powerpc/bits/floatn.h: Include <bits/long-double.h>.
[__NO_LONG_DOUBLE_MATH] (__HAVE_FLOAT128): Define to 0.
diff --git a/sysdeps/powerpc/bits/floatn.h b/sysdeps/powerpc/bits/floatn.h
index 44a9434..a293bfc 100644
--- a/sysdeps/powerpc/bits/floatn.h
+++ b/sysdeps/powerpc/bits/floatn.h
@@ -20,12 +20,13 @@
#define _BITS_FLOATN_H
#include <features.h>
+#include <bits/long-double.h>
/* Defined to 1 if the current compiler invocation provides a
floating-point type with the IEEE 754 binary128 format, and this glibc
includes corresponding *f128 interfaces for it. */
#if defined _ARCH_PWR8 && defined __LITTLE_ENDIAN__ && (_CALL_ELF == 2) \
- && defined __FLOAT128__
+ && defined __FLOAT128__ && !defined __NO_LONG_DOUBLE_MATH
# define __HAVE_FLOAT128 1
#else
# define __HAVE_FLOAT128 0
--
Joseph S. Myers
joseph@codesourcery.com