merge: free result of repo_get_merge_bases()

We call repo_get_merge_bases(), which allocates a commit_list, but never
free the result, causing a leak.

The obvious solution is to free it, but we need to look at the contents
of the first item to decide whether to leave the loop. One option is to
free it in both code paths. But since the commit that the list points to
is longer-lived than the list itself, we can just dereference it
immediately, free the list, and then continue with the existing logic.
This is about the same amount of code, but keeps the list management all
in one place.

This lets us mark a number of merge-related test scripts as leak-free.

Signed-off-by: Jeff King <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: peff

builtin/merge.c

@@ -1634,6 +1634,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 
 		for (j = remoteheads; j; j = j->next) {
 			struct commit_list *common_one;
+			struct commit *common_item;
 
 			/*
 			 * Here we *have* to calculate the individual
@@ -1643,7 +1644,9 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 			common_one = repo_get_merge_bases(the_repository,
 							  head_commit,
 							  j->item);
-			if (!oideq(&common_one->item->object.oid, &j->item->object.oid)) {
+			common_item = common_one->item;
+			free_commit_list(common_one);
+			if (!oideq(&common_item->object.oid, &j->item->object.oid)) {
 				up_to_date = 0;
 				break;
 			}

t/t4214-log-graph-octopus.sh

@@ -5,6 +5,7 @@ test_description='git log --graph of skewed left octopus merge.'
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-log-graph.sh
 

t/t4215-log-skewed-merges.sh

@@ -2,6 +2,7 @@
 
 test_description='git log --graph of skewed merges'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-log-graph.sh
 

t/t6009-rev-list-parent.sh

@@ -5,6 +5,7 @@ test_description='ancestor culling and limiting by parent number'
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 check_revlist () {

t/t6416-recursive-corner-cases.sh

@@ -5,6 +5,7 @@ test_description='recursive merge corner cases involving criss-cross merges'
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-merge.sh
 

t/t6433-merge-toplevel.sh

@@ -5,6 +5,7 @@ test_description='"git merge" top-level frontend'
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 t3033_reset () {

t/t6437-submodule-merge.sh

@@ -8,6 +8,7 @@ export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 GIT_TEST_FATAL_REGISTER_SUBMODULE_ODB=1
 export GIT_TEST_FATAL_REGISTER_SUBMODULE_ODB
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-merge.sh
 

t/t7602-merge-octopus-many.sh

@@ -4,6 +4,7 @@ test_description='git merge
 
 Testing octopus merge with more than 25 refs.'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success 'setup' '

t/t7603-merge-reduce-heads.sh

@@ -4,6 +4,7 @@ test_description='git merge
 
 Testing octopus merge when reducing parents to independent branches.'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 # 0 - 1

t/t7607-merge-state.sh

@@ -4,6 +4,7 @@ test_description="Test that merge state is as expected after failed merge"
 
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success 'Ensure we restore original state if no merge strategy handles it' '