llvm dev - Jul 2012 - [LLVMdev] Cross-compiling for cortex-m3: how do I get ride of -ccc-gcc-name ?

Hi there,

I'm using clang to cross compile for cortex-m3. I eventually managed to
do so with

clang++ -ccc-gcc-name arm-none-linux-gnueabi-g++ -ccc-host-triple
thumbv7m-none-gnueabi source.cpp -c -mcpu=cortex-m3

I would like to understand what -ccc-gcc-name does exactly and how
can I get ride of it?
>From what I understand, it's needed by the driver in order to find the
binutils
for calling the assembler and the linker. Is that correct?

After some grep'ing I ended up in gcc::Common::ConstructJob, where the
option
value is retrieved, but I'm not sure how does it fit with the rest.

How else can I tell llvm where to look for binutils?

Hope someone can save me a few hours around the codebase
with some insights.

Regards,
Salvatore

Making a symlink to clang in the same directory as the GCC / binutils (I'll
call it $ARM_BIN) called

arm-none-linux-gnueabi-clang (and one with clang++ too) 

and another link in the $ARM_BIN/../lib directory to clang directory located
under clang's lib (for includes)
should be enough.  


Gordon Keiser
Software Development Engineer
Arxan Technologies
gkeiser at arxan.com  www.arxan.com 


> -----Original Message-----
> From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at
cs.uiuc.edu]
> On Behalf Of salvatore benedetto
> Sent: Saturday, July 28, 2012 11:05 AM
> To: llvmdev at cs.uiuc.edu
> Subject: [LLVMdev] Cross-compiling for cortex-m3: how do I get ride of
-ccc-
> gcc-name ?
> 
> Hi there,
> 
> I'm using clang to cross compile for cortex-m3. I eventually managed to
do so
> with
> 
> clang++ -ccc-gcc-name arm-none-linux-gnueabi-g++ -ccc-host-triple
> thumbv7m-none-gnueabi source.cpp -c -mcpu=cortex-m3
> 
> I would like to understand what -ccc-gcc-name does exactly and how can I
get
> ride of it?
> 
> >From what I understand, it's needed by the driver in order to find
the
> >binutils
> for calling the assembler and the linker. Is that correct?
> 
> After some grep'ing I ended up in gcc::Common::ConstructJob, where the
> option value is retrieved, but I'm not sure how does it fit with the
rest.
> 
> How else can I tell llvm where to look for binutils?
> 
> Hope someone can save me a few hours around the codebase with some
> insights.
> 
> Regards,
> Salvatore
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev

On Mon, Jul 30, 2012 at 3:51 AM, Gordon Keiser <gkeiser at arxan.com>
wrote:
> Making a symlink to clang in the same directory as the GCC / binutils
(I'll call it $ARM_BIN) called
>
> arm-none-linux-gnueabi-clang (and one with clang++ too)
>
> and another link in the $ARM_BIN/../lib directory to clang directory
located under clang's lib (for includes)
> should be enough.
I'm sorry, I should have been more clear. I don't just want to get
right of the option itself, I want not to
have the need to a have a GCC cross-toolchain around.

I did download and cross compile binutils myself. I'd like llvm to use
that by default.

Is that possible?

Thanks,
Salvatore