installing M4-1.4.18.eb with --rpath fails if x86_64-pc-linux-gnu-gcc command is available

[boegel]

The RPATH sanity check fails because there is no (RPATH) section found in the output of readelf -d.

It seems that Autotools prefers using x86_64-pc-linux-gnu-gcc as compiler command when it is around (which it is in a Gentoo Prefix environment), and EasyBuild currently doesn't install a wrapper for this (only for gcc, g++, etc.).

This is probably only an issue when the system compiler is used, since in that case EasyBuild doesn't define $CC, $CXX and co. When $CC is set to gcc, the M4 build system uses gcc as expected, and then the issue does not occur (since there's an RPATH wrapper installed for gcc).

Two possible solutions:

• install wrappers for additional compiler commands when using the system compiler (cc, x86_64-pc-linux-gnu-gcc, and who knows what else)
• define $CC, $CXX & co to try and ensure the compiler wrappers are picked up

I'm in favor of the latter approach, since that's likely to be easier in the long run.

[lexming]

I agree with the second solution. It is possible to have multiple GCC versions installed at the same time in gentoo and there might be multiple binaries with names such as x86_64-pc-linux-gnu-gcc or several variations of that. However, at any time there is only one active installation that is controlled with gcc-config. So we should stick to the standard commands (eg gcc), which are just symlinks to the active GCC installation, to be sure that we are using the correct system compiler.