Clang: Replacing __attribute((__warning__())) by __attribute__((deprecated()))

[Olivier MARTIN <olivier at labapart dot com>]

Clang does not support the function attribute __warning__(), it raises 
the warning message: "warning: unknown attribute '__warning__' ignored"
A solution would be to replace the attribute __warning__() by 
deprecated().

Here is the GCC & Clang behaviour with some function attributes:

# The source code:
----------------------------
void func1(void) __attribute__((__warning__ ("the use of `func1' is 
dangerous; use `funcN' instead")));
void func2(void) __attribute__((deprecated("Deprecated func2; use 
`funcN` instead")));
void func3(void) __attribute__((warning("the use of `func3' is 
dangerous; use `funcN' instead")));

int main(void) {
  func1();
  func2();
  func3();
  return 0;
}
---------------------------

# With GCC:
---------------------------
mytest.c: In function âmainâ:
mytest.c:7:3: warning: âfunc2â is deprecated (declared at mytest.c:2): 
Deprecated func2; use `funcN` instead [-Wdeprecated-declarations]
   func2();
   ^
mytest.c:6:8: warning: call to âfunc1â declared with attribute warning: 
the use of `func1' is dangerous; use `funcN' instead [enabled by 
default]
   func1();
        ^
mytest.c:8:8: warning: call to âfunc3â declared with attribute warning: 
the use of `func3' is dangerous; use `funcN' instead [enabled by 
default]
   func3();
---------------------------

# With Clang:
---------------------------
mytest.c:1:33: warning: unknown attribute '__warning__' ignored 
[-Wunknown-attributes]
void func1(void) __attribute__((__warning__ ("the use of `func1' is 
dangerous; use `funcN' instead")));
                                ^
mytest.c:3:33: warning: unknown attribute 'warning' ignored 
[-Wunknown-attributes]
void func3(void) __attribute__((warning("the use of `func3' is 
dangerous; use `funcN' instead")));
                                ^
mytest.c:7:3: warning: 'func2' is deprecated: Deprecated func2; use 
`funcN` instead [-Wdeprecated-declarations]
  func2();
  ^
mytest.c:2:6: note: 'func2' has been explicitly marked deprecated here
void func2(void) __attribute__((deprecated("Deprecated func2; use 
`funcN` instead")));
     ^
3 warnings generated.
---------------------------

Here is the list of the function attributes supported by clang:
- http://clang.llvm.org/docs/LanguageExtensions.html
- http://clang.llvm.org/docs/AttributeReference.html

Are you happy by my suggestion of replacing __attribute((__warning__())) 
by __attribute__((deprecated()))?
I am happy to send a patch if needed.
Thanks,

--
Olivier MARTIN
http://labapart.com