[Bug c/59870] Gcc should warn conversion from "const char*" to "char*" for string literals

[chengniansun at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59870

--- Comment #6 from Chengnian Sun <chengniansun at gmail dot com> ---
(In reply to Harald van Dijk from comment #2)
> The type of a string literal in C is char[N], unlike in C++ where it is
> const char[N]. clang's -Weverything option enables -Wwrite-strings, which
> changes the type const char[N] and because of that makes the compiler not
> conform to the C standard. The same -Wwrite-strings option also exists in
> GCC already (in fact, I would be surprised if clang's name for the option
> didn't come from GCC), so I don't think there's anything in GCC that needs
> changing.
> 
> $ gcc -Wwrite-strings test.c
> test.c: In function ‘main’:
> test.c:4:19: warning: initialization discards ‘const’ qualifier from pointer
> target type [enabled by default]
>          char* s = "test";
>                    ^



Yes, this option works. 

However, one more question. Does "[enabled by default]" imply that this type of
warnings is enabled by default? If yes, then it is inconsistent with the
current setting of GCC flags (i.e., this flag should be explicitly enabled).