Subject: Re: [PATCH] Be nice with compilers that do not support runtime paths at all.

From: Junio C Hamano <[email-masked]>
Date: Wed, 03 Oct 2007 16:18:08 -0700

Benoit Sigoure <[email-masked]> writes:

> diff --git a/Makefile b/Makefile
> index a1fe443..7c6c453 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -100,6 +100,9 @@ all::
>  # that tells runtime paths to dynamic libraries;
>  # "-Wl,-rpath=/path/lib" is used instead.
>  #
> +# Define NO_RPATH if your dynamic loader doesn't support runtime paths at
> +# all.
> +#
>  # Define USE_NSEC below if you want git to care about sub-second file mtimes
>  # and ctimes. Note that you need recent glibc (at least 2.2.4) for this, and
>  # it will BREAK YOUR LOCAL DIFFS! show-diff and anything using it will likely

Thanks for this part;

> @@ -507,6 +510,7 @@ ifeq ($(uname_S),Darwin)
>  			BASIC_LDFLAGS += -L/opt/local/lib
>  		endif
>  	endif
> +        NO_RPATH = YesPlease
>  endif

I'll let Darwin users to fight the defaults for this part out.

> @@ -521,7 +525,10 @@ ifndef NO_CURL
>  	ifdef CURLDIR
>  		# Try "-Wl,-rpath=$(CURLDIR)/$(lib)" in such a case.
>  		BASIC_CFLAGS += -I$(CURLDIR)/include
> -		CURL_LIBCURL = -L$(CURLDIR)/$(lib) $(CC_LD_DYNPATH)$(CURLDIR)/$(lib) -lcurl
> +		CURL_LIBCURL = -L$(CURLDIR)/$(lib) -lcurl
> +ifndef NO_RPATH
> +		CURL_LIBCURL += $(CC_LD_DYNPATH)$(CURLDIR)/$(lib)
> +endif
>  	else
>  		CURL_LIBCURL = -lcurl
>  	endif

> @@ -539,7 +546,10 @@ endif
>  
>  ifdef ZLIB_PATH
>  	BASIC_CFLAGS += -I$(ZLIB_PATH)/include
> -	EXTLIBS += -L$(ZLIB_PATH)/$(lib) $(CC_LD_DYNPATH)$(ZLIB_PATH)/$(lib)
> +	EXTLIBS += -L$(ZLIB_PATH)/$(lib)
> +ifndef NO_RPATH
> +	EXTLIBS += $(CC_LD_DYNPATH)$(ZLIB_PATH)/$(lib)
> +endif
>  endif
>  EXTLIBS += -lz
>  

While these parts are ugly but correct, I think...

> @@ -547,7 +557,10 @@ ifndef NO_OPENSSL
>  	OPENSSL_LIBSSL = -lssl
>  	ifdef OPENSSLDIR
>  		BASIC_CFLAGS += -I$(OPENSSLDIR)/include
> -		OPENSSL_LINK = -L$(OPENSSLDIR)/$(lib) $(CC_LD_DYNPATH)$(OPENSSLDIR)/$(lib)
> +		OPENSSL_LINK = -L$(OPENSSLDIR)/$(lib)
> +ifndef NO_RPATH
> +		OPENSSL_LINK = $(CC_LD_DYNPATH)$(OPENSSLDIR)/$(lib)
> +endif
>  	else
>  		OPENSSL_LINK =
>  	endif

this and the ICONV one are missing s/=/+=/.

If we do not care about supporting too old GNU make, we can do
this by first adding this near the top:

        ifndef NO_RPATH
        LINKER_PATH = -L$(1) $(CC_LD_DYNPATH)$(1)
        else
        LINKER_PATH = -L$(1)
        endif

and then doing something like:

	CURL_LIBCURL = $(call LINKER_PATH,$(CURLDIR)/$(lib))
	OPENSSL_LINK = $(call LINKER_PATH,$(OPENSSLDIR)/$(lib))

to make it easier to read and less error prone.