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+/* Macros for controlling diagnostic output from the compiler.
+ Copyright (C) 2014-2018 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
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ 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/>. */
+
+#ifndef _LIBC_DIAG_H
+#define _LIBC_DIAG_H 1
+
+/* Ignore the value of an expression when a cast to void does not
+ suffice (in particular, for a call to a function declared with
+ attribute warn_unused_result). */
+#define ignore_value(x) \
+ ({ __typeof__ (x) __ignored_value = (x); (void) __ignored_value; })
+
+/* The macros to control diagnostics are structured like this, rather
+ than a single macro that both pushes and pops diagnostic state and
+ takes the affected code as an argument, because the GCC pragmas
+ work by disabling the diagnostic for a range of source locations
+ and do not work when all the pragmas and the affected code are in a
+ single macro expansion. */
+
+/* Push diagnostic state. */
+#define DIAG_PUSH_NEEDS_COMMENT _Pragma ("GCC diagnostic push")
+
+/* Pop diagnostic state. */
+#define DIAG_POP_NEEDS_COMMENT _Pragma ("GCC diagnostic pop")
+
+#define _DIAG_STR1(s) #s
+#define _DIAG_STR(s) _DIAG_STR1(s)
+
+/* Ignore the diagnostic OPTION. VERSION is the most recent GCC
+ version for which the diagnostic has been confirmed to appear in
+ the absence of the pragma (in the form MAJOR.MINOR for GCC 4.x,
+ just MAJOR for GCC 5 and later). Uses of this pragma should be
+ reviewed when the GCC version given is no longer supported for
+ building glibc; the version number should always be on the same
+ source line as the macro name, so such uses can be found with grep.
+ Uses should come with a comment giving more details of the
+ diagnostic, and an architecture on which it is seen if possibly
+ optimization-related and not in architecture-specific code. This
+ macro should only be used if the diagnostic seems hard to fix (for
+ example, optimization-related false positives). */
+#define DIAG_IGNORE_NEEDS_COMMENT(version, option) \
+ _Pragma (_DIAG_STR (GCC diagnostic ignored option))
+
+/* Similar to DIAG_IGNORE_NEEDS_COMMENT the following macro ignores the
+ diagnostic OPTION but only if optimizations for size are enabled.
+ This is required because different warnings may be generated for
+ different optimization levels. For example a key piece of code may
+ only generate a warning when compiled at -Os, but at -O2 you could
+ still want the warning to be enabled to catch errors. In this case
+ you would use DIAG_IGNORE_Os_NEEDS_COMMENT to disable the warning
+ only for -Os. */
+#ifdef __OPTIMIZE_SIZE__
+# define DIAG_IGNORE_Os_NEEDS_COMMENT(version, option) \
+ _Pragma (_DIAG_STR (GCC diagnostic ignored option))
+#else
+# define DIAG_IGNORE_Os_NEEDS_COMMENT(version, option)
+#endif
+
+#endif /* libc-diag.h */