kumquat-buildroot/package/glibc/glibc-2.28-18-g2339d6a55eb7a7e040ae888e906adc49eeb59eab/0001-sysdeps-ieee754-soft-fp-ignore-maybe-uninitialized-w.patch
Yegor Yefremov 3ac9baabf2 glibc: fix build breakage on soft-float configurations
On platforms with soft floating point glibc produces a compile time
warning (maybe-uninitialized) that will be regarded as an error.

Add upstream patch fixing this issue.

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
2018-10-11 09:32:49 +02:00

89 lines
3.3 KiB
Diff

From 4a06ceea33ecc220bbfe264d8f1e74de2f04e90d Mon Sep 17 00:00:00 2001
From: Martin Jansa <Martin.Jansa@gmail.com>
Date: Tue, 2 Oct 2018 15:38:43 +0000
Subject: [PATCH] sysdeps/ieee754/soft-fp: ignore maybe-uninitialized with -O
[BZ #19444]
* with -O, -O1, -Os it fails with:
In file included from ../soft-fp/soft-fp.h:318,
from ../sysdeps/ieee754/soft-fp/s_fdiv.c:28:
../sysdeps/ieee754/soft-fp/s_fdiv.c: In function '__fdiv':
../soft-fp/op-2.h:98:25: error: 'R_f1' may be used uninitialized in this function [-Werror=maybe-uninitialized]
X##_f0 = (X##_f1 << (_FP_W_TYPE_SIZE - (N)) | X##_f0 >> (N) \
^~
../sysdeps/ieee754/soft-fp/s_fdiv.c:38:14: note: 'R_f1' was declared here
FP_DECL_D (R);
^
../soft-fp/op-2.h:37:36: note: in definition of macro '_FP_FRAC_DECL_2'
_FP_W_TYPE X##_f0 _FP_ZERO_INIT, X##_f1 _FP_ZERO_INIT
^
../soft-fp/double.h:95:24: note: in expansion of macro '_FP_DECL'
# define FP_DECL_D(X) _FP_DECL (2, X)
^~~~~~~~
../sysdeps/ieee754/soft-fp/s_fdiv.c:38:3: note: in expansion of macro 'FP_DECL_D'
FP_DECL_D (R);
^~~~~~~~~
../soft-fp/op-2.h:101:17: error: 'R_f0' may be used uninitialized in this function [-Werror=maybe-uninitialized]
: (X##_f0 << (_FP_W_TYPE_SIZE - (N))) != 0)); \
^~
../sysdeps/ieee754/soft-fp/s_fdiv.c:38:14: note: 'R_f0' was declared here
FP_DECL_D (R);
^
../soft-fp/op-2.h:37:14: note: in definition of macro '_FP_FRAC_DECL_2'
_FP_W_TYPE X##_f0 _FP_ZERO_INIT, X##_f1 _FP_ZERO_INIT
^
../soft-fp/double.h:95:24: note: in expansion of macro '_FP_DECL'
# define FP_DECL_D(X) _FP_DECL (2, X)
^~~~~~~~
../sysdeps/ieee754/soft-fp/s_fdiv.c:38:3: note: in expansion of macro 'FP_DECL_D'
FP_DECL_D (R);
^~~~~~~~~
Build tested with Yocto for ARM, AARCH64, X86, X86_64, PPC, MIPS, MIPS64
with -O, -O1, -Os.
For AARCH64 it needs one more fix in locale for -Os.
[BZ #19444]
* sysdeps/ieee754/soft-fp/s_fdiv.c: Include <libc-diag.h> and use
DIAG_PUSH_NEEDS_COMMENT, DIAG_IGNORE_NEEDS_COMMENT and
DIAG_POP_NEEDS_COMMENT to disable -Wmaybe-uninitialized.
Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
---
sysdeps/ieee754/soft-fp/s_fdiv.c | 12 ++++++++++++
1 files changed, 12 insertions(+)
diff --git a/sysdeps/ieee754/soft-fp/s_fdiv.c b/sysdeps/ieee754/soft-fp/s_fdiv.c
index 341339f5ed..7a15cbeee6 100644
--- a/sysdeps/ieee754/soft-fp/s_fdiv.c
+++ b/sysdeps/ieee754/soft-fp/s_fdiv.c
@@ -25,6 +25,16 @@
#undef fdivl
#include <math-narrow.h>
+#include <libc-diag.h>
+
+/* R_f[01] are not set in cases where they are not used in packing,
+ but the compiler does not see that they are set in all cases where
+ they are used, resulting in warnings that they may be used
+ uninitialized. The location of the warning differs in different
+ versions of GCC, it may be where R is defined using a macro or it
+ may be where the macro is defined. This happens only with -O1. */
+DIAG_PUSH_NEEDS_COMMENT;
+DIAG_IGNORE_NEEDS_COMMENT (8, "-Wmaybe-uninitialized");
#include <soft-fp.h>
#include <single.h>
#include <double.h>
@@ -53,4 +63,6 @@ __fdiv (double x, double y)
CHECK_NARROW_DIV (ret, x, y);
return ret;
}
+DIAG_POP_NEEDS_COMMENT;
+
libm_alias_float_double (div)
--
2.17.0