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authorWaldemar Brodkorb <wbx@openadk.org>2023-07-14 11:06:52 +0200
committerWaldemar Brodkorb <wbx@openadk.org>2023-07-14 11:06:52 +0200
commit2c46c4ed23d333dcc0cea9fab47abf0167f8cf5a (patch)
treea51f8e2b0715584414f49f42f97df2853eb6b6e9 /libc/sysdeps/linux/common/bits
parent82fdc29f5fc430a725b922ac2086c02e918e269a (diff)
[PATCH] libc/sysdeps/linux/common/bits/wchar.h: resync with glibc, fix build issue with gcc 12
The current definition of __WCHAR_MIN and __WCHAR_MAX are only correct when wchar_t is an int. This is not the case on ARM/AArch64 where wchar_t is an unsigned int, or some other architectures where wchar_t is a long. The current incorrect definition causes a build issue for example when building mpd, which uses boost, with gcc 12.x: In file included from /home/thomas/buildroot/aarch64/host/aarch64-buildroot-linux-uclibc/sysroot/usr/include/boost/integer.hpp:20, from /home/thomas/buildroot/aarch64/host/aarch64-buildroot-linux-uclibc/sysroot/usr/include/boost/crc.hpp:42, from ../src/storage/StorageState.cxx:43: /home/thomas/buildroot/aarch64/host/aarch64-buildroot-linux-uclibc/sysroot/usr/include/boost/integer_traits.hpp:105:69: error: narrowing conversion of ‘-2147483648’ from ‘int’ to ‘wchar_t’ [-Wnarrowing] 105 | public detail::integer_traits_base<wchar_t, WCHAR_MIN, WCHAR_MAX> | ^ This issue was fixed in glibc in 2013, see bug report https://sourceware.org/bugzilla/show_bug.cgi?id=15036, and upstream commit https://sourceware.org/git/?p=glibc.git;a=commit;h=052aff95782fefe9c63566471063e8b20836bfb8. Since the i386-specific definition of __WCHAR_MIN and __WCHAR_MAX was also removed at the same time in glibc, we do the same as part of this commit. Reported-by: Clément Ramirez <clement.ramirez@bootlin.com> With-some-useful-help-from: Paul Kocialkowski <paul.kocialkowski@bootlin.com> Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Diffstat (limited to 'libc/sysdeps/linux/common/bits')
-rw-r--r--libc/sysdeps/linux/common/bits/wchar.h32
1 files changed, 28 insertions, 4 deletions
diff --git a/libc/sysdeps/linux/common/bits/wchar.h b/libc/sysdeps/linux/common/bits/wchar.h
index a3ff5319e..ce951d9b6 100644
--- a/libc/sysdeps/linux/common/bits/wchar.h
+++ b/libc/sysdeps/linux/common/bits/wchar.h
@@ -1,5 +1,5 @@
/* wchar_t type related definitions.
- Copyright (C) 2000 Free Software Foundation, Inc.
+ Copyright (C) 2000-2023 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
@@ -14,12 +14,36 @@
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
- <http://www.gnu.org/licenses/>. */
+ <https://www.gnu.org/licenses/>. */
#ifndef _BITS_WCHAR_H
#define _BITS_WCHAR_H 1
-#define __WCHAR_MIN (-2147483647 - 1)
-#define __WCHAR_MAX (2147483647)
+/* The fallback definitions, for when __WCHAR_MAX__ or __WCHAR_MIN__
+ are not defined, give the right value and type as long as both int
+ and wchar_t are 32-bit types. Adding L'\0' to a constant value
+ ensures that the type is correct; it is necessary to use (L'\0' +
+ 0) rather than just L'\0' so that the type in C++ is the promoted
+ version of wchar_t rather than the distinct wchar_t type itself.
+ Because wchar_t in preprocessor #if expressions is treated as
+ intmax_t or uintmax_t, the expression (L'\0' - 1) would have the
+ wrong value for WCHAR_MAX in such expressions and so cannot be used
+ to define __WCHAR_MAX in the unsigned case. */
+
+#ifdef __WCHAR_MAX__
+# define __WCHAR_MAX __WCHAR_MAX__
+#elif L'\0' - 1 > 0
+# define __WCHAR_MAX (0xffffffffu + L'\0')
+#else
+# define __WCHAR_MAX (0x7fffffff + L'\0')
+#endif
+
+#ifdef __WCHAR_MIN__
+# define __WCHAR_MIN __WCHAR_MIN__
+#elif L'\0' - 1 > 0
+# define __WCHAR_MIN (L'\0' + 0)
+#else
+# define __WCHAR_MIN (-__WCHAR_MAX - 1)
+#endif
#endif /* bits/wchar.h */