I'm currently compiling sources using --coverage, with GCC. The generated .gcno files (and the instrumented libraries) are to be packed in a RPM and the code coverage evaluated on another, target platform.
Now, I'm having a problem getting the coverage data, because when I run the programs calling the instrumented code, I get messages telling me that I have a version mismatch. They look like:
".gcda:Version mismatch - expected A85R got B12R"
Now, I've seen this question: GCOV Version mismatch - expected 700e got 408R which says I must use the same toolchain when compiling and when executing the code.
I'm compiling using gcc 11.2.1, and gcov --version says the same thing, on the source platform. On the target platform, gcc --version and gcov --version both give that very same version number.
The compiling and the testing is done on the same "physical" machine, but on different Docker containers. On both of them, the GCC version and gcov version are the same
I've done further testing: even on the Docker container where we compile, we cannot run the coverage, and get the same error. Or, to be more precise, when compiled using gcc 11, it will say "version mismatch". However, when compiled using gcc 8.5, it works.
The setup is that we have the GCC 11 toolset, which requires gcc 8.5 to install. By default, gcc 8.5 is enabled, and you have to use a script (provided by the gcc 11 toolset) to enable the later. That script updates different variables, like the PATH, LIBRARY_PATH, etc., to look at GCC 11 first.
However, I'm pretty sure it doesn't upgrade the libc.so library, and that it's the cause of the problem: I compiled two of our simplest libs (each of them having no dependencies whatsoever, except libc) with gcc 11, in coverage mode. Then I compiled a simple test program, without coverage, calling some functions from the two instrumented libs. I checked (with elfread -d), the program only links to these two libs (and libc).
Calling this test program while on the compilation container results in the Version mismatch error, which would lead me to conclude that our libc.so isn't compatible with gcc 11.
I wonder if there is a way to get a "native" gcc 11, instead of a "toolkit" package which has to be installed over a gcc 8.5 (my colleague in charge of creating the Docker containers tells me that for gcc 9 and above, there are only "toolkit" packages, requiring gcc 8.5 to install).
Our target architecture runs on Rocky Linux, and I think our development architecture is a Redhat, if it has any importance here.