Running:

$ clang --version
clang version 4.0.1 (tags/RELEASE_401/final 305264)

$ cat a.c
int main() {}

$ clang -m32 a.c
/usr/bin/ld: skipping incompatible
/usr/bin/../lib64/gcc/x86_64-suse-linux/7/../../../libc.so when searching for
-lc
/lib/libc.so.6: error adding symbols: File format not recognized
clang-4.0.1: error: linker command failed with exit code 1 (use -v to see
invocation)

I've noticed we have openSUSE specific patches:
https://build.opensuse.org/package/view_file/openSUSE:Factory/llvm4/clang-resourcedirs.patch?expand=1
https://build.opensuse.org/package/view_file/openSUSE:Factory/llvm4/assume-opensuse.patch?expand=1

But it does not work properly with -m32. Note the code in DetectDistro.cpp
checks for /etc/SuSE-release, which is legacy. One should use /etc/os-release.
I can fix that after we resolve this issue.

Thanks,
Martin