Compiling libMesh

Compiling libMesh requires a proper environment. Lets verify a few things before attempting to build it (or possibly re-build it in your case):

Verify you have a proper compiler present:

Linux:

which $CC
/opt/moose/mpich-4.0.2/gcc-12.2.1/bin/mpicc

mpicc -show
gcc -I/opt/moose/mpich-4.0.2/gcc-12.2.1/include -L/opt/moose/mpich-4.0.2/gcc-12.2.1/lib -Wl,-rpath -Wl,/opt/moose/mpich-4.0.2/gcc-12.2.1/lib -Wl,--enable-new-dtags -lmpi

which gcc
/opt/moose/gcc-12.2.1/bin/gcc

Macintosh:

which $CC
/opt/moose/mpich-4.0.2/clang-__LLVM__/bin/mpicc

mpicc -show
clang -Wl,-commons,use_dylibs -I/opt/moose/mpich-4.0.2/clang-__LLVM__/include -L/opt/moose/mpich-4.0.2/clang-__LLVM__/lib -lmpi -lpmpi

which clang
/opt/moose/llvm-__LLVM__/bin/clang

What you are looking for is that which and mpicc -show are returning proper paths. If these paths are not set, or which is not returning anything, see Modules for help on setting up a proper environment. Once set up, return here and verify the above commands return the proper messages.

Check that PETSC_DIR is set and does exist:
- Linux:
```
echo $PETSC_DIR
/opt/moose/petsc-__PETSC_DEFAULT__/mpich-__MPICH___gcc-12.2.1-opt

file $PETSC_DIR
/opt/moose/petsc-__PETSC_DEFAULT__/mpich-__MPICH___gcc-12.2.1-opt: directory
```
- Macintosh:
```
echo $PETSC_DIR
/opt/moose/petsc-__PETSC_DEFAULT__/mpich-__MPICH___clang-__LLVM__-opt

file $PETSC_DIR
/opt/moose/petsc-__PETSC_DEFAULT__/mpich-__MPICH___clang-__LLVM__-opt: directory
```
- If echo $PETSC_DIR returns nothing, this would indicate your environment is not complete. See Modules for help on setting up a proper environment. Once set up, return here and verify the above commands return the proper messages.
- If file $PETSC_DIR returns an error (possible if you are performing a Manual Install), it would appear you have not yet ran configure. Configure builds this directory.

With the above all taken care of, try to build libMesh:
```
cd moose/scripts
./update_and_rebuild_libmesh.sh
```
If you encounter errors during this step, we would like to hear from you! Please seek help on the MOOSE Discussion forum. Provide the diagnostic and libMesh configure logs. Those two files can be found in the following locations:
- moose/libmesh/build/config.log
- moose/scripts/libmesh_diagnostic.log

If libMesh built successfully, return to the beginning of the step that lead you here, and try that step again.

Compiling libMesh