From e54655a20e4f53e6a723deb09d5a5a36c315f2b3 Mon Sep 17 00:00:00 2001 From: Diego Novillo Date: Fri, 16 Apr 2010 08:37:55 -0400 Subject: [PATCH] Clarify what happens with an unrecognized -Wno- option From-SVN: r158413 --- gcc/doc/invoke.texi | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 8dcba6ee0c8..39920a84db3 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -2807,6 +2807,15 @@ two forms, whichever is not the default. For further, language-specific options also refer to @ref{C++ Dialect Options} and @ref{Objective-C and Objective-C++ Dialect Options}. +When an unrecognized warning label is requested, for example +@option{-Wunknwon-warning}, GCC will emit a diagnostic stating +that the option is not recognized. However, if the @samp{-Wno-} form +is used, the behavior is slightly different: No diagnostic will be +produced for @option{-Wno-unknown-warning} unless other diagnostics +are being produced. This allows the use of new @option{-Wno-} options +with old compilers, but if something goes wrong, the compiler will +warn that an unrecognized option was used. + @table @gcctabopt @item -pedantic @opindex pedantic -- 2.11.4.GIT