Suppress more variable-set-but-not-used warnings from clang 15.

Mop up assorted set-but-not-used warnings in the back branches.
This includes back-patching relevant fixes from commit 152c9f7b8
the rest of the way, but there are also several cases that did not
appear in HEAD.  Some of those we'd fixed in a retail way but not
back-patched, and others I think just got rewritten out of existence
during nearby refactoring.

While here, also back-patch b1980f6d0 (PL/Tcl: Fix compiler warnings
with Tcl 8.6) into 9.2, so that that branch compiles warning-free
with modern Tcl.

Per project policy, this is a candidate for back-patching into
out-of-support branches: it suppresses annoying compiler warnings
but changes no behavior.  Hence, back-patch all the way to 9.2.

Discussion: https://postgr.es/m/514615.1663615243@sss.pgh.pa.us

diff --git a/src/backend/optimizer/util/var.c b/src/backend/optimizer/util/var.c
index 42d10388ae780f2c598851eec0e67e81188e014c..109a0d978fd32f6c3b443924d37100fae4cacd93 100644 (file)
--- a/src/backend/optimizer/util/var.c
+++ b/src/backend/optimizer/util/var.c
@@ -773,16 +773,13 @@ flatten_join_alias_vars_mutator(Node *node,
            RowExpr    *rowexpr;
            List       *fields = NIL;
            List       *colnames = NIL;
-           AttrNumber  attnum;
            ListCell   *lv;
            ListCell   *ln;
 
-           attnum = 0;
            Assert(list_length(rte->joinaliasvars) == list_length(rte->eref->colnames));
            forboth(lv, rte->joinaliasvars, ln, rte->eref->colnames)
            {
                newvar = (Node *) lfirst(lv);
-               attnum++;
                /* Ignore dropped columns */
                if (newvar == NULL)
                    continue;

diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index 54de07218153c311a4bab0c0851f4eedbd291453..c37e43a9044d840b230dc5cdf3067f155bc4a3e5 100644 (file)
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -4373,7 +4373,6 @@ AttrDefaultFetch(Relation relation)
    HeapTuple   htup;
    Datum       val;
    bool        isnull;
-   int         found;
    int         i;
 
    ScanKeyInit(&skey,
@@ -4384,7 +4383,6 @@ AttrDefaultFetch(Relation relation)
    adrel = table_open(AttrDefaultRelationId, AccessShareLock);
    adscan = systable_beginscan(adrel, AttrDefaultIndexId, true,
                                NULL, 1, &skey);
-   found = 0;
 
    while (HeapTupleIsValid(htup = systable_getnext(adscan)))
    {
@@ -4399,8 +4397,6 @@ AttrDefaultFetch(Relation relation)
                elog(WARNING, "multiple attrdef records found for attr %s of rel %s",
                     NameStr(attr->attname),
                     RelationGetRelationName(relation));
-           else
-               found++;
 
            val = fastgetattr(htup,
                              Anum_pg_attrdef_adbin,