Merge pull request libgit2#4420 from pks-t/pks/strict-aliasing

refcount: make refcounting conform to aliasing rules

Author: carlosmn

src/diff_generate.c

@@ -411,7 +411,7 @@ static git_diff_generated *diff_generated_alloc(
 	if ((diff = git__calloc(1, sizeof(git_diff_generated))) == NULL)
 		return NULL;
 
-	GIT_REFCOUNT_INC(diff);
+	GIT_REFCOUNT_INC(&diff->base);
 	diff->base.type = GIT_DIFF_TYPE_GENERATED;
 	diff->base.repo = repo;
 	diff->base.old_src = old_iter->type;

src/diff_parse.c

@@ -36,7 +36,7 @@ static git_diff_parsed *diff_parsed_alloc(void)
 	if ((diff = git__calloc(1, sizeof(git_diff_parsed))) == NULL)
 		return NULL;
 
-	GIT_REFCOUNT_INC(diff);
+	GIT_REFCOUNT_INC(&diff->base);
 	diff->base.type = GIT_DIFF_TYPE_PARSED;
 	diff->base.strcomp = git__strcmp;
 	diff->base.strncomp = git__strncmp;

src/patch_generate.c

@@ -139,7 +139,7 @@ static int patch_generated_alloc_from_diff(
 
 	if (!(error = patch_generated_init(patch, diff, delta_index))) {
 		patch->flags |= GIT_PATCH_GENERATED_ALLOCATED;
-		GIT_REFCOUNT_INC(patch);
+		GIT_REFCOUNT_INC(&patch->base);
 	} else {
 		git__free(patch);
 		patch = NULL;

src/patch_parse.c

@@ -1084,7 +1084,7 @@ int git_patch_parse(
 	patch->base.diff_opts.new_prefix = patch->new_prefix;
 	patch->base.diff_opts.flags |= GIT_DIFF_SHOW_BINARY;
 
-	GIT_REFCOUNT_INC(patch);
+	GIT_REFCOUNT_INC(&patch->base);
 	*out = &patch->base;
 
 done:

src/repository.c

@@ -10,7 +10,6 @@
 #include <ctype.h>
 
 #include "git2/object.h"
-#include "git2/refdb.h"
 #include "git2/sys/repository.h"
 
 #include "common.h"
@@ -25,6 +24,7 @@
 #include "refs.h"
 #include "filter.h"
 #include "odb.h"
+#include "refdb.h"
 #include "remote.h"
 #include "merge.h"
 #include "diff_driver.h"

src/util.h

@@ -297,22 +297,22 @@ typedef struct {
 typedef void (*git_refcount_freeptr)(void *r);
 
 #define GIT_REFCOUNT_INC(r) { \
-	git_atomic_inc(&((git_refcount *)(r))->refcount);	\
+	git_atomic_inc(&(r)->rc.refcount);	\
 }
 
 #define GIT_REFCOUNT_DEC(_r, do_free) { \
-	git_refcount *r = (git_refcount *)(_r); \
+	git_refcount *r = &(_r)->rc; \
 	int val = git_atomic_dec(&r->refcount); \
 	if (val <= 0 && r->owner == NULL) { do_free(_r); } \
 }
 
 #define GIT_REFCOUNT_OWN(r, o) { \
-	((git_refcount *)(r))->owner = o; \
+	(r)->rc.owner = o; \
 }
 
-#define GIT_REFCOUNT_OWNER(r) (((git_refcount *)(r))->owner)
+#define GIT_REFCOUNT_OWNER(r) ((r)->rc.owner)
 
-#define GIT_REFCOUNT_VAL(r) git_atomic_get(&((git_refcount *)(r))->refcount)
+#define GIT_REFCOUNT_VAL(r) git_atomic_get((r)->rc.refcount)
 
 
 static signed char from_hex[] = {