diff --git a/test/old/testdir/Makefile b/test/old/testdir/Makefile
index d73571f463..22c2a9dcc9 100644
--- a/test/old/testdir/Makefile
+++ b/test/old/testdir/Makefile
@@ -116,6 +116,7 @@ CLEAN_FILES := *.out \
   *.tlog            \
   opt_test.vim      \
   test_result.log   \
+  gen_opt_test.log  \
   $(CLEANUP_FILES)  \
   $(RM_ON_RUN)      \
   $(RM_ON_START)    \
@@ -158,8 +159,8 @@ GEN_OPT_DEPS = gen_opt_test.vim ../../../src/nvim/options.lua ../../../runtime/d
 
 opt_test.vim: $(GEN_OPT_DEPS)
 	$(NVIM_PRG) -e -s -u NONE $(NO_INITS) -S $(GEN_OPT_DEPS)
-	@if test -f test.log; then \
-		cat test.log; \
+	@if test -f gen_opt_test.log; then \
+		cat gen_opt_test.log; \
 		exit 1; \
 	fi
 
diff --git a/test/old/testdir/gen_opt_test.vim b/test/old/testdir/gen_opt_test.vim
index af968181e3..9cea88bcec 100644
--- a/test/old/testdir/gen_opt_test.vim
+++ b/test/old/testdir/gen_opt_test.vim
@@ -527,7 +527,7 @@ catch
   " Append errors to test.log
   let error = $'Error: {v:exception} in {v:throwpoint}'
   echo error
-  split test.log
+  split gen_opt_test.log
   call append('$', error)
   write
 endtry