Ease building with custom includedir.

[crayxt]

If you specify build_includedir to be inside of $(build_prefix)/usr and not in $(build_prefix)/include then include files of gmp and LLVM are not installed to build_includedir but to $(build_prefix)/include.
The only thing missing is specifying pcre.h header file for pcre_h.jl. I am still thinking on it.

[crayxt]

Cast @nalimilan

[ViralBShah]

Cc: @staticfloat

[staticfloat]

@crayxt Could you give us a little more info as to what the idea behind this PR is? I think I agree with most of these changes, (except perhaps for the LLVM_CONFIG changes; what are those changes for?) but it would help to know why these changes are necessary for you.

[crayxt]

@staticfloat I apologize for not providing good explanation from the beginning.
The main idea is when you specify custom $(build_includedir), most of the packages from deps directory follow that location, except for llvm and gmp. They store own header files into hardcoded path $(build_prefix)/include. So I tried to make all deps packages behave the same way.

As for llvm-config change, it addresses the similar issue of hardcoded path, this time for binary files. If I change $(build_bindir) to my own value, the old location of llvm-config would be incorrect, but $(build_bindir)/llvm-config remains correct when USE_SYSTEM_LLVM=0.

[nalimilan]

Makes much sense, but I think @staticfloat was curious about the situation in which you need it. It's always interesting to understand changes.

BTW, if the llvm-config change is about binaries, you should make the commit message more general.

[staticfloat]

Ah, I see; LLVMROOT is just $(build_prefix).

These are all good changes. It sounds like your pcre.h changes are not complete though. Please let me know when the changes are complete so I can test.

[crayxt]

@staticfloat Pull request updated. I couldn't find a better way other than using ifeq switch.

[staticfloat]

I don't think your sed invocation works right on OSX. When I run this branch, I get:

sed: 1: "Makefile.in": invalid command code M
make[2]: *** [gmp-5.1.3/config.status] Error 1
make[1]: *** [julia-release] Error 2
make: *** [release] Error 2
make build_includedir=$(pwd)/usr/include2 took 05:37:07

I think it's because of these lines which unfortunately don't work on OSX because sed -i requires a file extension afterward. I think if you just change this to -ibackup or something, it should work.

[tkelman]

Do you really need to use sed there? Can't an extra configure argument accomplish the same thing?

[crayxt]

@tkelman I think you are right, I will check

[crayxt]

@staticfloat Pull request updated. I suppose there is no reason to wait for Travis results, as it uses system libs. Sadly, I don't have OSX to check this.
@tkelman I couldn't make it work with only supplying flags to configure script.

[staticfloat]

How delightfully ironic that we use these convoluted regexes to patch PCRE.

[staticfloat]

Oddly enough, I couldn't find the magic invocations to configure or make to get it to put the header files where we wanted them either. This is good for me, I'm going to merge.