diff options
Diffstat (limited to 'gcc/doc')
| -rw-r--r-- | gcc/doc/extend.texi | 11 | ||||
| -rw-r--r-- | gcc/doc/invoke.texi | 8 |
2 files changed, 16 insertions, 3 deletions
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi index e03eaf9faad..43e91afe8b4 100644 --- a/gcc/doc/extend.texi +++ b/gcc/doc/extend.texi @@ -5774,9 +5774,12 @@ returns the value that had previously been in memory. That is, @smallexample @{ tmp = *ptr; *ptr @var{op}= value; return tmp; @} -@{ tmp = *ptr; *ptr = ~tmp & value; return tmp; @} // nand +@{ tmp = *ptr; *ptr = ~(tmp & value); return tmp; @} // nand @end smallexample +@emph{Note:} GCC 4.4 and later implement @code{__sync_fetch_and_nand} +builtin as @code{*ptr = ~(tmp & value)} instead of @code{*ptr = ~tmp & value}. + @item @var{type} __sync_add_and_fetch (@var{type} *ptr, @var{type} value, ...) @itemx @var{type} __sync_sub_and_fetch (@var{type} *ptr, @var{type} value, ...) @itemx @var{type} __sync_or_and_fetch (@var{type} *ptr, @var{type} value, ...) @@ -5794,9 +5797,13 @@ return the new value. That is, @smallexample @{ *ptr @var{op}= value; return *ptr; @} -@{ *ptr = ~*ptr & value; return *ptr; @} // nand +@{ *ptr = ~(*ptr & value); return *ptr; @} // nand @end smallexample +@emph{Note:} GCC 4.4 and later implement @code{__sync_nand_and_fetch} +builtin as @code{*ptr = ~(*ptr & value)} instead of +@code{*ptr = ~*ptr & value}. + @item bool __sync_bool_compare_and_swap (@var{type} *ptr, @var{type} oldval @var{type} newval, ...) @itemx @var{type} __sync_val_compare_and_swap (@var{type} *ptr, @var{type} oldval @var{type} newval, ...) @findex __sync_bool_compare_and_swap diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index cc66b45c14b..476ab8cf92a 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -257,7 +257,7 @@ Objective-C and Objective-C++ Dialects}. -Wsign-compare -Wsign-conversion -Wstack-protector @gol -Wstrict-aliasing -Wstrict-aliasing=n @gol -Wstrict-overflow -Wstrict-overflow=@var{n} @gol --Wswitch -Wswitch-default -Wswitch-enum @gol +-Wswitch -Wswitch-default -Wswitch-enum -Wsync-nand @gol -Wsystem-headers -Wtrigraphs -Wtype-limits -Wundef -Wuninitialized @gol -Wunknown-pragmas -Wno-pragmas -Wunreachable-code @gol -Wunused -Wunused-function -Wunused-label -Wunused-parameter @gol @@ -3127,6 +3127,12 @@ and lacks a @code{case} for one or more of the named codes of that enumeration. @code{case} labels outside the enumeration range also provoke warnings when this option is used. +@item -Wsync-nand +@opindex Wsync-nand +@opindex Wno-sync-nand +Warn when @code{__sync_fetch_and_nand} and @code{__sync_nand_and_fetch} +built-in functions are used. These functions changed semantics in GCC 4.4. + @item -Wtrigraphs @opindex Wtrigraphs @opindex Wno-trigraphs |