git-compat-util: drop UNLEAK() annotation

There are two users of `UNLEAK()` left in our codebase:

  - In "builtin/clone.c", annotating the `repo` variable. That leak has
    already been fixed though as you can see in the context, where we do
    know to free `repo_to_free`.

  - In "builtin/diff.c", to unleak entries of the `blob[]` array. That
    leak has also been fixed, because the entries we assign to that
    array come from `rev.pending.objects`, and we do eventually release
    `rev`.

This neatly demonstrates one of the issues with `UNLEAK()`: it is quite
easy for the annotation to become stale. A second issue is that its
whole intent is to paper over leaks. And while that has been a necessary
evil in the past, because Git was leaking left and right, it isn't
really much of an issue nowadays where our test suite has no known leaks
anymore.

Remove the last two users and drop the now-unused `UNLEAK()` annotation.

Signed-off-by: Patrick Steinhardt <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: pks-t

builtin/clone.c

@@ -1586,7 +1586,6 @@ int cmd_clone(int argc,
 	free(dir);
 	free(path);
 	free(repo_to_free);
-	UNLEAK(repo);
 	junk_mode = JUNK_LEAVE_ALL;
 
 	transport_ls_refs_options_release(&transport_ls_refs_options);

builtin/diff.c

@@ -628,6 +628,5 @@ int cmd_diff(int argc,
 	release_revisions(&rev);
 	object_array_clear(&ent);
 	symdiff_release(&sdiff);
-	UNLEAK(blob);
 	return result;
 }

git-compat-util.h

@@ -1527,26 +1527,6 @@ int cmd_main(int, const char **);
 int common_exit(const char *file, int line, int code);
 #define exit(code) exit(common_exit(__FILE__, __LINE__, (code)))
 
-/*
- * You can mark a stack variable with UNLEAK(var) to avoid it being
- * reported as a leak by tools like LSAN or valgrind. The argument
- * should generally be the variable itself (not its address and not what
- * it points to). It's safe to use this on pointers which may already
- * have been freed, or on pointers which may still be in use.
- *
- * Use this _only_ for a variable that leaks by going out of scope at
- * program exit (so only from cmd_* functions or their direct helpers).
- * Normal functions, especially those which may be called multiple
- * times, should actually free their memory. This is only meant as
- * an annotation, and does nothing in non-leak-checking builds.
- */
-#ifdef SUPPRESS_ANNOTATED_LEAKS
-void unleak_memory(const void *ptr, size_t len);
-#define UNLEAK(var) unleak_memory(&(var), sizeof(var))
-#else
-#define UNLEAK(var) do {} while (0)
-#endif
-
 #define z_const
 #include <zlib.h>
 

usage.c

@@ -350,18 +350,3 @@ void bug_fl(const char *file, int line, const char *fmt, ...)
 	trace2_cmd_error_va(fmt, ap);
 	va_end(ap);
 }
-
-#ifdef SUPPRESS_ANNOTATED_LEAKS
-void unleak_memory(const void *ptr, size_t len)
-{
-	static struct suppressed_leak_root {
-		struct suppressed_leak_root *next;
-		char data[FLEX_ARRAY];
-	} *suppressed_leaks;
-	struct suppressed_leak_root *root;
-
-	FLEX_ALLOC_MEM(root, data, ptr, len);
-	root->next = suppressed_leaks;
-	suppressed_leaks = root;
-}
-#endif