From: Ramsay Jones Date: Mon, 29 Apr 2013 23:01:09 GMT Subject: Re: [PATCH 6/6] compat/nedmalloc: Fix compiler warnings on linux Message-ID: <517EFBB5.9040502@ramsay1.demon.co.uk> In-Reply-To: <7v7gjmqwxn.fsf@alter.siamese.dyndns.org> Junio C Hamano wrote: > Ramsay Jones writes: > >> On linux, when the build variable USE_NED_ALLOCATOR is set, gcc >> issues the following warnings: >> >> In file included from compat/nedmalloc/nedmalloc.c:63: >> .../malloc.c.h: In function 'mmap_resize': >> .../malloc.c.h:3762: warning: implicit declaration of function 'mremap' >> .../malloc.c.h: In function 'sys_trim': >> .../malloc.c.h:4195: warning: comparison between pointer and integer >> >> The warnings are caused by the header not enabling the >> (conditional) declaration of the mremap() function. The declaration >> can be enabled by defining the _GNU_SOURCE symbol prior to including >> certain system header files. In particular, it may not be sufficient >> to simply define _GNU_SOURCE just prior to including the >> header. (e.g. defining the symbol after including will >> be completely ineffective.) >> >> In order to suppress the warnings, we define the _GNU_SOURCE symbol >> at the start of the malloc.c.h header file. >> >> Signed-off-by: Ramsay Jones >> --- > > Hmmmm, is this even worth worrying about? I somehow thought this > was only meant to replace malloc on non GNU systems... Maybe not. I certainly won't be using it on Linux. But I wanted to test the previous patch on Linux and it didn't compile cleanly, so ... (It passed all tests BTW). ATB, Ramsay Jones