Thread

[PATCH v6 1/2] Add static assertions about size of GinTernaryValue vs bool

Peter Eisentraut <peter_e@gmx.net> — 2017-12-19T18:54:05Z

We need these to be the same because some code casts between pointers to
them.
---
 src/backend/utils/adt/tsginidx.c | 4 +++-
 src/include/access/gin.h         | 4 ++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/backend/utils/adt/tsginidx.c b/src/backend/utils/adt/tsginidx.c
index de59e6417e..00e32b2570 100644
--- a/src/backend/utils/adt/tsginidx.c
+++ b/src/backend/utils/adt/tsginidx.c
@@ -309,7 +309,9 @@ gin_tsquery_consistent(PG_FUNCTION_ARGS)
 		 * query.
 		 */
 		gcv.first_item = GETQUERY(query);
-		gcv.check = check;
+		StaticAssertStmt(sizeof(GinTernaryValue) == sizeof(bool),
+						 "sizes of GinTernaryValue and bool are not equal");
+		gcv.check = (GinTernaryValue *) check;
 		gcv.map_item_operand = (int *) (extra_data[0]);
 		gcv.need_recheck = recheck;
 
diff --git a/src/include/access/gin.h b/src/include/access/gin.h
index 0acdb88241..3d8a130b69 100644
--- a/src/include/access/gin.h
+++ b/src/include/access/gin.h
@@ -51,8 +51,8 @@ typedef struct GinStatsData
 /*
  * A ternary value used by tri-consistent functions.
  *
- * For convenience, this is compatible with booleans. A boolean can be
- * safely cast to a GinTernaryValue.
+ * This must be of the same size as a bool because some code will cast a
+ * pointer to a bool to a pointer to a GinTernaryValue.
  */
 typedef char GinTernaryValue;
 

base-commit: 17bb62501787c56e0518e61db13a523d47afd724
-- 
2.16.2


--------------B00F3D5C7F79BB1E3887F7C5
Content-Type: text/plain; charset=UTF-8; x-mac-type="0"; x-mac-creator="0";
 name="v6-0002-Use-stdbool.h-if-suitable.patch"
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment;
 filename="v6-0002-Use-stdbool.h-if-suitable.patch"