COMPILER_PATH question

COMPILER_PATH question

[Chih Wang]

Hi all,

I'm experiencing a weird behavior and would appreciate some guidance.

We are using gcc v 4.4.6 (plus necessary packages to support c++
compilation) installed in a non-standard location due to company
policy. When I first logged into the test box, I can compile and link
a test c++ program without any problem. However, as soon as I source
our project specific resource file, the same code fails to compile
with the following error:

> gcc test.cc -o myout -lstdc++
gcc: error trying to exec 'cc1plus': execvp: No such file or directory

After some digging around, it appears that the issue is caused by a
different value in COMPILER_PATH as returned by running echo "" | gcc
- -xc -v -E.

Before sourcing our environment file, I got:
COMPILER_PATH=/swdepot/2012-Q2/37178099/SDK/usr/bin/../libexec/gcc/x86_64-redhat-linux/4.4.6/:/swdepot/2012-Q2/37178099/SDK/usr/bin/../libexec/gcc/:/usr/libexec/gcc/x86_64-redhat-linux/4.4.6/:/usr/libexec/gcc/x86_64-redhat-linux/

After sourcing:
COMPILER_PATH=/usr/libexec/gcc/x86_64-redhat-linux/4.4.6/:/usr/libexec/gcc/x86_64-redhat-linux/

After sourcing out environment file, somehow gcc would no longer look
for compilers under /swdepot/.... location where gcc toolchains are
installed. But interestingly, the same is not true for for either
LIBRARY_PATH or include path, where before/after both still include
locations where gcc is installed.

Our environment file does not set anything for COMPILER_PATH, and the
only major differences I can see when comparing the before/after
environments is some difference in PATH and LD_LIBRARY_PATH.

My questions:
1. What would affect gcc's ability to deduce COMPILER_PATH?
2. If it's something in my PATH or LD_LIBRARY_PATH value, what could
be the culprit?
3. Any other environment variable I should look out for?

Thanks,
Chih

Re: COMPILER_PATH question

[Ian Lance Taylor]

Chih Wang <wangcyc@gmail.com> writes:

> 1. What would affect gcc's ability to deduce COMPILER_PATH?

It's set based on the name used to run gcc and on the environment
variable GCC_EXEC_PREFIX.

> 2. If it's something in my PATH or LD_LIBRARY_PATH value, what could
> be the culprit?
> 3. Any other environment variable I should look out for?

See above.

Ian

Re: COMPILER_PATH question

[Jonathan Wakely]

On 26 May 2012 00:08, Chih Wang wrote:
>
>> gcc test.cc -o myout -lstdc++

In case it's not obvious, a simpler form of that command is:

g++ test.cc -o myout

Re: COMPILER_PATH question

[Chih Wang]

Thanks guys.

I found the problem and thought I'd share this info.

In my environment I used a variable to indicate where the GCC
toolchain is installed. The name I picked was GCC_ROOT which I thought
was random. But somehow, setting GCC_ROOT resulted in shortened
COMPILER_PATH and it no longer included the path where gcc was
located. Strangely, this behavior only happens for COMPILER_PATH but
not include or library path which still show the location where gcc is
installed.

Using a different name to indicate my local gcc location solved my problem.

Regards,
Chih

On Fri, May 25, 2012 at 4:54 PM, Jonathan Wakely <jwakely.gcc@gmail.com> wrote:
> On 26 May 2012 00:08, Chih Wang wrote:
>>
>>> gcc test.cc -o myout -lstdc++
>
> In case it's not obvious, a simpler form of that command is:
>
> g++ test.cc -o myout