diff options
Diffstat (limited to '')
| -rw-r--r-- | lib/error.in.h | 103 |
1 files changed, 98 insertions, 5 deletions
diff --git a/lib/error.in.h b/lib/error.in.h index 9a520f1..51f8caf 100644 --- a/lib/error.in.h +++ b/lib/error.in.h @@ -1,5 +1,5 @@ /* Declarations for error-reporting functions. - Copyright (C) 1995-1997, 2003, 2006, 2008-2023 Free Software Foundation, + Copyright (C) 1995-1997, 2003, 2006, 2008-2024 Free Software Foundation, Inc. This file is part of the GNU C Library. @@ -18,9 +18,9 @@ #ifndef _@GUARD_PREFIX@_ERROR_H -#if __GNUC__ >= 3 -@PRAGMA_SYSTEM_HEADER@ -#endif +/* No @PRAGMA_SYSTEM_HEADER@ here, because it would prevent + -Wimplicit-fallthrough warnings for missing FALLTHROUGH after error(...) + or error_at_line(...) invocations. */ /* The include_next requires a split double-inclusion guard. */ #if @HAVE_ERROR_H@ @@ -30,11 +30,15 @@ #ifndef _@GUARD_PREFIX@_ERROR_H #define _@GUARD_PREFIX@_ERROR_H -/* This file uses _GL_ATTRIBUTE_FORMAT. */ +/* This file uses _GL_ATTRIBUTE_ALWAYS_INLINE, _GL_ATTRIBUTE_FORMAT, + _GL_ATTRIBUTE_MAYBE_UNUSED. */ #if !_GL_CONFIG_H_INCLUDED #error "Please include config.h first." #endif +/* Get 'unreachable'. */ +#include <stddef.h> + /* Get _GL_ATTRIBUTE_SPEC_PRINTF_STANDARD, _GL_ATTRIBUTE_SPEC_PRINTF_SYSTEM. */ #include <stdio.h> @@ -46,6 +50,35 @@ # define _GL_ATTRIBUTE_SPEC_PRINTF_ERROR _GL_ATTRIBUTE_SPEC_PRINTF_SYSTEM #endif +/* Helper macro for supporting the compiler's control flow analysis better. + It evaluates its arguments only once. + Test case: Compile copy-file.c with "gcc -Wimplicit-fallthrough". */ +#if defined __GNUC__ || defined __clang__ +/* Use 'unreachable' to tell the compiler when the function call does not + return. */ +# define __gl_error_call1(function, status, ...) \ + ((function) (status, __VA_ARGS__), \ + (status) != 0 ? unreachable () : (void) 0) +/* If STATUS is a not a constant, the function call may or may not return; + therefore -Wimplicit-fallthrough will produce a warning. Use a compound + statement in order to evaluate STATUS only once. + If STATUS is a constant, we don't use a compound statement, because that + would trigger a -Wimplicit-fallthrough warning even when STATUS is != 0, + when not optimizing. This causes STATUS to be evaluated twice, but + that's OK since it does not have side effects. */ +# define __gl_error_call(function, status, ...) \ + (__builtin_constant_p (status) \ + ? __gl_error_call1 (function, status, __VA_ARGS__) \ + : __extension__ \ + ({ \ + int const __errstatus = status; \ + __gl_error_call1 (function, __errstatus, __VA_ARGS__); \ + })) +#else +# define __gl_error_call(function, status, ...) \ + (function) (status, __VA_ARGS__) +#endif + #ifdef __cplusplus extern "C" { #endif @@ -63,6 +96,11 @@ _GL_FUNCDECL_RPL (error, void, _GL_ATTRIBUTE_FORMAT ((_GL_ATTRIBUTE_SPEC_PRINTF_ERROR, 3, 4))); _GL_CXXALIAS_RPL (error, void, (int __status, int __errnum, const char *__format, ...)); +# ifndef _GL_NO_INLINE_ERROR +# undef error +# define error(status, ...) \ + __gl_error_call (rpl_error, status, __VA_ARGS__) +# endif #else # if ! @HAVE_ERROR@ _GL_FUNCDECL_SYS (error, void, @@ -71,6 +109,30 @@ _GL_FUNCDECL_SYS (error, void, # endif _GL_CXXALIAS_SYS (error, void, (int __status, int __errnum, const char *__format, ...)); +# ifndef _GL_NO_INLINE_ERROR +# ifdef error +/* Only gcc ≥ 4.7 has __builtin_va_arg_pack. */ +# if _GL_GNUC_PREREQ (4, 7) +# pragma GCC diagnostic push +# pragma GCC diagnostic ignored "-Wattributes" +_GL_ATTRIBUTE_MAYBE_UNUSED +static void +_GL_ATTRIBUTE_ALWAYS_INLINE +_GL_ATTRIBUTE_FORMAT ((_GL_ATTRIBUTE_SPEC_PRINTF_ERROR, 3, 4)) +_gl_inline_error (int __status, int __errnum, const char *__format, ...) +{ + return error (__status, __errnum, __format, __builtin_va_arg_pack ()); +} +# pragma GCC diagnostic pop +# undef error +# define error(status, ...) \ + __gl_error_call (_gl_inline_error, status, __VA_ARGS__) +# endif +# else +# define error(status, ...) \ + __gl_error_call (error, status, __VA_ARGS__) +# endif +# endif #endif #if __GLIBC__ >= 2 _GL_CXXALIASWARN (error); @@ -90,6 +152,11 @@ _GL_FUNCDECL_RPL (error_at_line, void, _GL_CXXALIAS_RPL (error_at_line, void, (int __status, int __errnum, const char *__filename, unsigned int __lineno, const char *__format, ...)); +# ifndef _GL_NO_INLINE_ERROR +# undef error_at_line +# define error_at_line(status, ...) \ + __gl_error_call (rpl_error_at_line, status, __VA_ARGS__) +# endif #else # if ! @HAVE_ERROR_AT_LINE@ _GL_FUNCDECL_SYS (error_at_line, void, @@ -100,6 +167,32 @@ _GL_FUNCDECL_SYS (error_at_line, void, _GL_CXXALIAS_SYS (error_at_line, void, (int __status, int __errnum, const char *__filename, unsigned int __lineno, const char *__format, ...)); +# ifndef _GL_NO_INLINE_ERROR +# ifdef error_at_line +/* Only gcc ≥ 4.7 has __builtin_va_arg_pack. */ +# if _GL_GNUC_PREREQ (4, 7) +# pragma GCC diagnostic push +# pragma GCC diagnostic ignored "-Wattributes" +_GL_ATTRIBUTE_MAYBE_UNUSED +static void +_GL_ATTRIBUTE_ALWAYS_INLINE +_GL_ATTRIBUTE_FORMAT ((_GL_ATTRIBUTE_SPEC_PRINTF_ERROR, 5, 6)) +_gl_inline_error_at_line (int __status, int __errnum, const char *__filename, + unsigned int __lineno, const char *__format, ...) +{ + return error_at_line (__status, __errnum, __filename, __lineno, __format, + __builtin_va_arg_pack ()); +} +# pragma GCC diagnostic pop +# undef error_at_line +# define error_at_line(status, ...) \ + __gl_error_call (_gl_inline_error_at_line, status, __VA_ARGS__) +# endif +# else +# define error_at_line(status, ...) \ + __gl_error_call (error_at_line, status, __VA_ARGS__) +# endif +# endif #endif _GL_CXXALIASWARN (error_at_line); |