system.h & warnings

[Jeffrey A Law]

  In message < 199804021620.LAA18789@caip.rutgers.edu >you write:
  > 	One thing I'd like to bring up, the test you used in genoutput.c
  > to see if __attribute__ should be used only checks __GNUC__.  This can
  > fail for stage1 compilers which are gcc but are older versions.  E.g. 
  > these can be either gcc installed by the user or the default compiler
  > (like maybe nextstep? I'll bet it fails there.)
Good point.


  > 	I'd like to put something in gansidecl.h to do a rigorous test
  > once.  Then one can use __attribute__, or macros based on it, more freely. 
Yes, I think putting this into gansidecl.h would be fine.

However, I don't want to go littering too much of the source code
with attributes.  I don't mind in the generated files because we
very rarely have to look at them :-)

  > 	Should I make a patch to put the following in gansidecl.h?
  > 
  > 		--Kaveh
  > 
  >  > #if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 7)
  >  > # define __attribute__(x)
  >  > #endif
  >  > 
  >  > #define ATTRIBUTE_UNUSED __attribute__ ((unused))
  >  > 
  >  > #define ATTRIBUTE_PRINTF(m, n) __attribute__ ((format (__printf__, m, n)
  > ))
  >  > #define ATTRIBUTE_PRINTF_1 ATTRIBUTE_PRINTF(1, 2)
  >  > #define ATTRIBUTE_PRINTF_2 ATTRIBUTE_PRINTF(2, 3)
  >  > #define ATTRIBUTE_PRINTF_3 ATTRIBUTE_PRINTF(3, 4)
Why bother with the ATTRIBUTE_UNUSED macro?  It isn't significantly
simpler or easier to read than __attribute__ ((unused)).

jeff