From: Junio C Hamano <gitster@pobox.com>
Date: Fri, 13 Sep 2013 22:06:42 GMT
Subject: Re: [PATCH] git-compat-util: Avoid strcasecmp() being inlined
Message-ID: <xmqqli30idfx.fsf@gitster.dls.corp.google.com>
In-Reply-To: <CAHGBnuM=QqLxPNNZmoL1jG+oAm2y6o=AuBtkH+FRwZ_8ahGC+w@mail.gmail.com>

Sebastian Schuberth <sschuberth@gmail.com> writes:

> On Fri, Sep 13, 2013 at 10:01 PM, Junio C Hamano <gitster@pobox.com> wrote:
>
>>> I don't like the idea of introducing a compat/mingw/string.h because
>>> of two reasons: You would have to add a conditional to include that
>>> string.h instead of the system one anyway,
>>
>> With -Icompat/mingw passed to the compiler, which is a bog-standard
>> technique we already use to supply headers the system forgot to
>> supply or override buggy headers the system is shipped with, you do
>> not have to change any "#include <string.h>".
>>
>> Am I mistaken?
>
> Ah, that would work I guess, but you'd still need the include_next.

You can explicitly include the system header from your compatibility
layer, i.e. 

	=== compat/mingw/string.h ===

	#define __NO_INLINE__

	#ifdef SYSTEM_STRING_H_HEADER
        #include SYSTEM_STRING_H_HEADER
        #else
        #include_next <string.h>
	#endif

and then in config.mak.uname, do something like this:

	ifneq (,$(findstring MINGW,$(uname_S)))
	ifndef SYSTEM_STRING_H_HEADER
	SYSTEM_STRING_H_HEADER = "C:\\llvm\include\string.h"
        endif

	COMPAT_CFLAGS += -DSYSTEM_STRING_H_HEADER=$(SYSTEM_STRING_H_HEADER)
	endif

People who have the system header file at different paths can
further override SYSTEM_STRING_H_HEADER in their config.mak.

That would help compilers targetting mingw that do not support
"#include_next" without spreading the damage to other people's
systems, I think.