[LLVMdev] Question about uninstalling LLVM

[Bill Wendling]

On Oct 27, 2006, at 9:31 PM, Seung Jae Lee wrote:

> Hello. Nice to meet you.
> My name is Seung Jae Lee, a graduate student in UIUC CEE, who is  
> working in NCSA for the present.
> Nowadays I am trying to develop LLVM backend to spit out CHiMPS  
> assembly code. In the process, I installed LLVM codes on my home  
> directory in the host computer. But I don't think it was installed  
> properly. While bootstrapping the LLVM C/C++ Front-End, I met  
> several errors, so I think it's better for me to remove what has  
> been done and to re-install LLVM.
> In fact, there are LLVM-GCC in the host computer in other account  
> but there are no LLVM suite. For this reason, I tried to have my  
> own LLVM. Eventually I failed. I think there might be conflict  
> between mine and the main directory.
> For this reason, I think it would be greatly helpful even if I have  
> quite a bit of your advice.
> Would you mind replying to me?
> Thank you very much.
>
> Seung Jae Lee
>
Hi Seung,

In addition to what John wrote, I wanted to ask: Do you need to  
compile the LLVM-GCC front-end yourself? If not, then you could just  
use the binary distribution provided by the http://llvm.org/ website.  
(This is assuming that you're running on Linux, Mac, FreeBSD, or  
Mingw. The website is here:

	http://llvm.org/releases/download.html#1.8

You'll get a tar ball which you can unpack anywhere. You can then  
just set your PATH environment variable to point to that before  
pointing to the system's LLVM-GCC front-end.

If you really *really* need to compile the LLVM-GCC front-end on your  
own, you should follow the directions here:

	http://llvm.org/docs/CFEBuildInstrs.html

There's also a README.LLVM in the LLVM-GCC source tree which you'll  
need to read as well.

The order of compilations goes like this:

	- Download the LLVM-GCC binary distribution.
	- Unpack the binary.
	- Add the binary to your PATH environment variable.
		- If you're using the LLVM-GCC4 front-end (recommended), then CD  
into its bin/ directory and create sym-links to the c++, cpp, g++,  
and gcc executables called llvm-c++, llvm-cpp, llvm-g++, and llvm-gcc  
resp.
	- Download LLVM's source tree
	- Build the LLVM source tree.
	- Attain enlightenment. :-)

If you need to build the front-end, you'll have to build it AFTER you  
build the LLVM source. Again, don't do this unless you absolutely  
*need* to.

I hope this helps!

-bw