Aws Lambda: C++ custom runtime - /usr/bin/ld: cannot find /usr/lib64/libc_nonshared.a

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
25/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
aws, cpp, linux
Domain
build-system, cloud

Research direction

Start with the reported execl invocation and the AWS Lambda layer paths under /opt/gpp3, then inspect why the linker searches /usr/lib64 instead of the layer directory. Reproduce the g++48 command and verify that libc_nonshared.a is resolved from /opt/gpp3/usr/lib64; the issue is done when the sample compilation succeeds in the Lambda environment.

Written by the indexing model from the issue text.

Description

I am trying to add g++ inside AWS Lambda C++ custom runtime.

Now g++ requires .so (shared libraries) files as well as .a (static libraries).

For this, I installed g++ inside chroot directory (directory gpp) on the Amazon Linux machine.

Now, I created another directory that has bin, usr, lib, and lib64 directories (taken from chroot directory). I created a zip of this directory, uploaded to s3 (as it is more than 50MB), and created a Lambda layer using this zip directory.

Now, after adding this layer in the lambda function, I am trying to run.

execl("/opt/usr/bin/g++48", "/opt/usr/bin/g++48", "-Wall",  "/tmp/hello.cpp","-o", "/tmp/hello.o",
 "-I/opt/gpp3/usr/include/", (char *) 0)

Using the above g++ is able to find shared libraries as well as header files but it is not able to find the static library.

/usr/bin/ld: cannot find /usr/lib64/libc_nonshared.a
collect2: error: ld returned 1 exit status

libc_nonshared.a exists inside /opt/gpp3/usr/lib64/ but it is searching in /usr/lib64/.

I tried providing full path in g++ command as -L/opt/gpp3/usr/lib64/libc_nonshared.a and
-L/opt/gpp3/usr/lib64/libc_nonshared and -L/opt/gpp3/usr/lib64/

But none of them works. Any help is deeply appreciated.

Dominant language
C++
Stars
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Forks
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Avg merge
1h 16m
Merged PRs (30d)
2

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