Remove useless pstrdups in untransformRelOptions

alvherre · alvherre · commit 6710e83a675e · 2022-09-13T11:59:31.000+02:00
The two strings are already a single palloc'd chunk, not freed; there's no reason to allocate separate copies that have the same lifetime. This code is only called in short-lived memory contexts (except in some cases in TopTransactionContext, which is still short-lived enough not to really matter), and typically only for short arrays, so the memory or computation saved is likely negligible. However, let's fix it to avoid leaving a bad example of code to copy. This is the only place I could find where we're doing this with makeDefElem(). Reported-by: Junwang Zhao <zhjwpku@gmail.com> Discussion: https://postgr.es/m/20220909142050.3vv2hjekppk265dd@alvherre.pgsql
diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
@@ -1357,9 +1357,9 @@ untransformRelOptions(Datum options)
 		if (p)
 		{
 			*p++ = '\0';
-			val = (Node *) makeString(pstrdup(p));
+			val = (Node *) makeString(p);
 		}
-		result = lappend(result, makeDefElem(pstrdup(s), val, -1));
+		result = lappend(result, makeDefElem(s, val, -1));
 	}
 
 	return result;

Original file line number	Diff line number	Diff line change
`@@ -1357,9 +1357,9 @@ untransformRelOptions(Datum options)`
`1357`	`1357`	`if (p)`
`1358`	`1358`	`{`
`1359`	`1359`	`*p++ = '\0';`
`1360`		`- val = (Node *) makeString(pstrdup(p));`
	`1360`	`+ val = (Node *) makeString(p);`
`1361`	`1361`	`}`
`1362`		`- result = lappend(result, makeDefElem(pstrdup(s), val, -1));`
	`1362`	`+ result = lappend(result, makeDefElem(s, val, -1));`
`1363`	`1363`	`}`
`1364`	`1364`
`1365`	`1365`	`return result;`