PR c/18624

[pf3gnuchains/gcc-fork.git] / gcc / doc / invoke.texi

diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index d356daa..67a1b60 100644 (file)
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -262,7 +262,7 @@ Objective-C and Objective-C++ Dialects}.
 -Wunknown-pragmas  -Wno-pragmas @gol
 -Wunsuffixed-float-constants  -Wunused  -Wunused-function @gol
 -Wunused-label  -Wunused-parameter -Wno-unused-result -Wunused-value  -Wunused-variable @gol
--Wvariadic-macros -Wvla @gol
+-Wunused-but-set-parameter -Wunused-but-set-variable -Wvariadic-macros -Wvla @gol
 -Wvolatile-register-var  -Wwrite-strings}
 
 @item C and Objective-C-only Warning Options
@@ -2926,7 +2926,8 @@ name is still supported, but the newer name is more descriptive.)
 -Wsign-compare  @gol
 -Wtype-limits  @gol
 -Wuninitialized  @gol
--Wunused-parameter @r{(only with} @option{-Wunused} @r{or} @option{-Wall}@r{)}  @gol
+-Wunused-parameter @r{(only with} @option{-Wunused} @r{or} @option{-Wall}@r{)} @gol
+-Wunused-but-set-parameter @r{(only with} @option{-Wunused} @r{or} @option{-Wall}@r{)}  @gol
 }
 
 The option @option{-Wextra} also prints warning messages for the
@@ -3321,6 +3322,31 @@ Warn if any trigraphs are encountered that might change the meaning of
 the program (trigraphs within comments are not warned about).
 This warning is enabled by @option{-Wall}.
 
+@item -Wunused-but-set-parameter
+@opindex Wunused-but-set-parameter
+@opindex Wno-unused-but-set-parameter
+Warn whenever a function parameter is assigned to, but otherwise unused
+(aside from its declaration).
+
+To suppress this warning use the @samp{unused} attribute
+(@pxref{Variable Attributes}).
+
+This warning is also enabled by @option{-Wunused} together with
+@option{-Wextra}.
+
+@item -Wunused-but-set-variable
+@opindex Wunused-but-set-variable
+@opindex Wno-unused-but-set-variable
+Warn whenever a local variable is assigned to, but otherwise unused
+(aside from its declaration).
+This warning is enabled by @option{-Wall}.
+
+To suppress this warning use the @samp{unused} attribute
+(@pxref{Variable Attributes}).
+
+This warning is also enabled by @option{-Wunused}, which is enabled
+by @option{-Wall}.
+
 @item -Wunused-function
 @opindex Wunused-function
 @opindex Wno-unused-function