[Bug other/50647] gcc/system.h: wrong prototype for sbrk

[joseph at codesourcery dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50647

--- Comment #3 from joseph at codesourcery dot com <joseph at codesourcery dot com> 2011-10-07 21:49:58 UTC ---
In general the declarations in system.h are expected to be used only for 
very archaic hosts that do not have prototypes in their system headers.  
For such hosts, int is probably the right argument type; this prototype 
should never be used for modern hosts.  As such, the prototype should 
probably remain unchanged; no host that actually has intptr_t should ever 
see it.  The problem would be that the declaration was not detected; we 
need more details of the host (including whether you were e.g. building 
natively or building a Canadian cross).

AC_USE_SYSTEM_EXTENSIONS should already ensure all appropriate feature 
test macros are defined for known hosts.