This is the mail archive of the
glibc-cvs@sourceware.org
mailing list for the glibc project.
GNU C Library master sources branch master updated. glibc-2.20-75-g0022e68
- From: jsm28 at sourceware dot org
- To: glibc-cvs at sourceware dot org
- Date: 9 Oct 2014 01:07:56 -0000
- Subject: GNU C Library master sources branch master updated. glibc-2.20-75-g0022e68
This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GNU C Library master sources".
The branch, master has been updated
via 0022e688d082761a1e15b19121303cafbdad33ec (commit)
from 73e28d9c885fdfed91e6d70c4aab7e8e801818e3 (commit)
Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
revisions in full, below.
- Log -----------------------------------------------------------------
http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=0022e688d082761a1e15b19121303cafbdad33ec
commit 0022e688d082761a1e15b19121303cafbdad33ec
Author: Joseph Myers <joseph@codesourcery.com>
Date: Thu Oct 9 01:07:10 2014 +0000
soft-fp: Fix _FP_TO_INT latent bug in overflow handling.
This patch fixes a latent bug in _FP_TO_INT regarding handling of
arguments with maximum exponent (infinities and NaNs). If the maximum
exponent is below that calculated as an overflow threshold, such
values would incorrectly be treated as normal values for the purposes
of the conversion. This could not occur for any of the conversions
actually occurring in glibc, libgcc or the Linux kernel (the maximum
exponent for float is, just, big enough to ensure overflow for
unsigned __int128), but would apply if soft-fp were used for IEEE
binary16. Appropriate checks are inserted to ensure that the maximum
exponent is always treated as an overflowing exponent, and never as a
normal one.
Tested for powerpc-nofpu that the disassembly of installed shared
libraries is unchanged by this patch.
* soft-fp/op-common.h (_FP_TO_INT): Ensure maximum exponent is
treated as invalid conversion, not as normal exponent.
diff --git a/ChangeLog b/ChangeLog
index f95e3ed..18d1cbc 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
2014-10-09 Joseph Myers <joseph@codesourcery.com>
+ * soft-fp/op-common.h (_FP_TO_INT): Ensure maximum exponent is
+ treated as invalid conversion, not as normal exponent.
+
* soft-fp/op-common.h (_FP_CMP_CHECK_NAN): New macro.
(_FP_CMP): Add extra argument EX. Call _FP_CMP_CHECK_NAN.
(_FP_CMP_EQ): Likewise.
diff --git a/soft-fp/op-common.h b/soft-fp/op-common.h
index e62558e..e0a108a 100644
--- a/soft-fp/op-common.h
+++ b/soft-fp/op-common.h
@@ -1368,7 +1368,9 @@
else \
FP_SET_EXCEPTION (FP_EX_INEXACT); \
} \
- else if (X##_e >= _FP_EXPBIAS_##fs + rsize - (rsigned > 0 || X##_s) \
+ else if (X##_e >= (_FP_EXPMAX_##fs < _FP_EXPBIAS_##fs + rsize \
+ ? _FP_EXPMAX_##fs \
+ : _FP_EXPBIAS_##fs + rsize - (rsigned > 0 || X##_s)) \
|| (!rsigned && X##_s)) \
{ \
/* Overflow or converting to the most negative integer. */ \
@@ -1385,7 +1387,10 @@
r = ~r; \
} \
\
- if (rsigned && X##_s && X##_e == _FP_EXPBIAS_##fs + rsize - 1) \
+ if (_FP_EXPBIAS_##fs + rsize - 1 < _FP_EXPMAX_##fs \
+ && rsigned \
+ && X##_s \
+ && X##_e == _FP_EXPBIAS_##fs + rsize - 1) \
{ \
/* Possibly converting to most negative integer; check the \
mantissa. */ \
-----------------------------------------------------------------------
Summary of changes:
ChangeLog | 3 +++
soft-fp/op-common.h | 9 +++++++--
2 files changed, 10 insertions(+), 2 deletions(-)
hooks/post-receive
--
GNU C Library master sources