[PATCH] Skip gdb.base/libsegfault.exp on Cygwin

[Pedro Alves <pedro@palves.net>]

Running gdb.base/libsegfault.exp on Cygwin, in parallel mode causes
badness:

 $ make check-parallel TESTS="gdb.base/libsegfault.exp"
 ...
 Running /home/alves/gdb/src/gdb/testsuite/gdb.base/libsegfault.exp ...
       0 [main] expect 6611 C:\cygwin64\bin\expect.exe: *** fatal error in forked process - error while loading shared libraries: libSegFault.so: cannot open shared object file: No such file or directory
				*** starting '"C:\cygwin64\bin\dumper.exe" -n "C:\cygwin64\bin\expect.exe" 8012' for pid 6611, tid 7992
 *** continuing pid 6611
 parent: sync byte write: broken pipe
 make[1]: *** [Makefile:320: check/gdb.base/libsegfault.exp] Error 255
 make[1]: Target 'do-check-parallel' not remade because of errors.
 make[1]: Leaving directory '/home/alves/rocm/gdb/build-cygwin-testsuite'
 outputs/gdb.base/libsegfault/gdb.sum: no recognised summary line
 outputs/gdb.base/libsegfault/gdb.log: no recognised summary line
 make: *** [Makefile:260: check-parallel] Error 2
 $

I.e., Expect's spawn fails, and that brings down the whole Expect
process, for some reason.  The result is that we end up with
incomplete gdb.sum/gdb.log files, which dg-extract-results.sh can't
process.  Since libSegFault.so is a glibc feature that doesn't exist
on Cygwin, just skip the test there.

Change-Id: I44bdbffa25a5d21c5019418b68776d334a57be26
---
 gdb/testsuite/gdb.base/libsegfault.exp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/gdb/testsuite/gdb.base/libsegfault.exp b/gdb/testsuite/gdb.base/libsegfault.exp
index eab12ff57e1..808ab046bc5 100644
--- a/gdb/testsuite/gdb.base/libsegfault.exp
+++ b/gdb/testsuite/gdb.base/libsegfault.exp
@@ -24,6 +24,12 @@
 # the local machine.
 require {!is_remote host}
 
+# On Cygwin, the testcase would somehow end up trying to preload
+# libSegFault.so into the Expect process, which would fail and crash
+# it.  Since libSegFault.so is a glibc feature that doesn't exist on
+# Cygwin, just skip testing there.
+require {!expr {[isbuild "*-*-cygwin*"] && [ishost "*-*-cygwin*"]}}
+
 # Spawn GDB with LIB preloaded with LD_PRELOAD.  CMDLINE_OPTS are
 # command line options passed to GDB.
 
-- 
2.49.0