http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50134
--- Comment #10 from Manuel López-Ibáñez <manu at gcc dot gnu.org> 2012-05-15
12:23:50 UTC ---
Nonetheless, this is a patch that explains the current situation:
--- gcc/doc/invoke.texi (revision 187462)
+++ gcc/doc/invoke.texi (working copy)
@@ -4413,21 +4413,26 @@ This warning is also enabled by @option{
@item -Wmissing-prototypes @r{(C and Objective-C only)}
@opindex Wmissing-prototypes
@opindex Wno-missing-prototypes
Warn if a global function is defined without a previous prototype
declaration. This warning is issued even if the definition itself
-provides a prototype. The aim is to detect global functions that
-are not declared in header files.
+provides a prototype. The aim is to detect global functions that are
+not declared in header files, independently of whether the declaration
+is a prototype. This option does not apply to C++ because there is no
+concept of prototype. Use @option{-Wmissing-declarations} to detect
+missing declarations in C++.
@item -Wmissing-declarations
@opindex Wmissing-declarations
@opindex Wno-missing-declarations
Warn if a global function is defined without a previous declaration.
-Do so even if the definition itself provides a prototype.
-Use this option to detect global functions that are not declared in
-header files. In C++, no warnings are issued for function templates,
-or for inline functions, or for functions in anonymous namespaces.
+Do so even if the definition itself provides a prototype. Use this
+option to detect global functions that are not declared in header
+files. In C, this option does not warn if there is a previous
+non-prototype declaration; use @option{-Wmissing-prototype} to detect
+those. In C++, no warnings are issued for function templates, or for
+inline functions, or for functions in anonymous namespaces.
