The libctf-regression/open-error-free.c test works by interposing malloc
and counting mallocs and frees across libctf operations. This only
works under suitably-interposable mallocs on systems supporting
dlsym (RTLD_NEXT, ...), so its operation is restricted to glibc
systems for now, but also it interacts badly with valgrind, which
interposes malloc itself. Detect a running valgrind and skip the test.
Add new facilities allowing libctf lookup tests to declare themselves
unsupported, by printing "UNSUPPORTED: " and then some meaningful
message instead of their normal output.
libctf/
* configure.ac: Check for <valgrind/valgrind.h>.
* config.h.in: Regenerate.
* configure: Likewise.
* testsuite/lib/ctf-lib.exp (run_lookup_test): Add support for
UNSUPPORTED tests.
* testsuite/libctf-regression/open-error-free.c: When running
under valgrind, this test is unsupported.
9f0fb75b8e