Analyse following RPM build log snippet. Describe contents accurately, without speculation or suggestions for resolution.            
Your analysis must be as concise as possible, while keeping relevant information intact.
Snippet: 
++ cat cvs.log
Possible precedence problem between ! and pattern match (m//) at /builddir/build/BUILD/git-2.49.0-build/git-2.49.0/git-cvsserver line 5015.
++ return 1
error: last command exited with $?=1
not ok 30 - cvs diff -r v1 -u

#	
#		( cd cvswork && cvs -f diff -r v1 -u >../cvsDiff.out 2>../cvs.log ) &&
#		test_must_be_empty cvsDiff.out &&
#		test_must_be_empty cvs.log
#	
expecting success of 9402.31 'cvs diff -N -r v2 -u': 
	( cd cvswork && ! cvs -f diff -N -r v2 -u >../cvsDiff.out 2>../cvs.log ) &&
	test_must_be_empty cvs.log &&
	test -s cvsDiff.out &&
	check_diff cvsDiff.out v2 v1 >check_diff.out 2>&1

Here build fails, because there is warning "Possible precedence problem between ! and pattern match (m//) ".