RPM generation error “Missing build-id”

I came across this error while trying to build an RPM for apptainer on my system, which is older than what is supported by the authors. The compilation process seems to complete successfully, but at the end, no RPM is generated. These messages are shown:

    error: Missing build-id in /home/swbuild/rpmbuild/BUILDROOT/apptainer-1.1.3-1.el8.x86_64/usr/libexec/apptainer/bin/squashfuse_ll
    error: Generating build-id links failed

    RPM build errors:
        Macro expanded in comment on line 97: %{?el7}

        Missing build-id in /home/swbuild/rpmbuild/BUILDROOT/apptainer-1.1.3-1.el8.x86_64/usr/libexec/apptainer/bin/squashfuse_ll
        Generating build-id links failed

This is because older versions of GCC do not include the build-id by default. The fix is to add LDFLAGS="-Wl,--build-id" to the configure line in the .spec.in file, e.g.

    FLAGS=-std=c99 LDFLAGS="-Wl,--build-id" ./configure --enable-multithreading