Check the RHS when building a set (#8159)

Fixes #2669

compiler/sem.nim

@@ -76,7 +76,7 @@ template semIdeForTemplateOrGeneric(c: PContext; n: PNode;
 proc fitNodePostMatch(c: PContext, formal: PType, arg: PNode): PNode =
   result = arg
   let x = result.skipConv
-  if x.kind in {nkPar, nkTupleConstr} and formal.kind != tyExpr:
+  if x.kind in {nkPar, nkTupleConstr, nkCurly} and formal.kind != tyExpr:
     changeType(c, x, formal, check=true)
   else:
     result = skipHiddenSubConv(result)

tests/sets/t2669.nim

@@ -0,0 +1,6 @@
+discard """
+line: 6
+errormsg: "cannot convert 6 to range 1..5(int8)"
+"""
+
+var c: set[range[1i8..5i8]] = {1i8, 2i8, 6i8}