Fixes #10727. (#10728)

compiler/semgnrc.nim

@@ -352,7 +352,12 @@ proc semGenericStmt(c: PContext, n: PNode,
     openScope(c)
     n.sons[L - 2] = semGenericStmt(c, n.sons[L-2], flags, ctx)
     for i in countup(0, L - 3):
-      addTempDecl(c, n.sons[i], skForVar)
+      if (n.sons[i].kind == nkVarTuple):
+        for s in n.sons[i]:
+          if (s.kind == nkIdent):
+            addTempDecl(c,s,skForVar)
+      else:
+        addTempDecl(c, n.sons[i], skForVar)
     openScope(c)
     n.sons[L - 1] = semGenericStmt(c, n.sons[L-1], flags, ctx)
     closeScope(c)

tests/tuples/tfortupleunpack.nim

@@ -8,6 +8,7 @@ output: '''
 113283
 @[(88, 99, 11), (88, 99, 11)]
 @[(7, 6, -28), (7, 6, -28)]
+12
 '''
 """
 
@@ -36,4 +37,7 @@ for i, (a, b, c) in x.mpairs:
   c = -28
 echo x
 
-
+proc test[n]() =
+  for (a,b) in @[(1,2)]:
+    echo a,b
+test[string]()