declaredlocs followup: handle cannot instantiate errors (#17745)

Author: timotheecour

compiler/semtypes.nim

@@ -1463,9 +1463,9 @@ proc semGeneric(c: PContext, n: PNode, s: PSym, prev: PType): PType =
     matches(c, n, copyTree(n), m)
 
     if m.state != csMatch:
-      let err = "cannot instantiate " & typeToString(t) & "\n" &
-                "got: <" & describeArgs(c, n) & ">\n" &
-                "but expected: <" & describeArgs(c, t.n, 0) & ">"
+      var err = "cannot instantiate "
+      err.addTypeHeader(c.config, t)
+      err.add "\ngot: <$1>\nbut expected: <$2>" % [describeArgs(c, n), describeArgs(c, t.n, 0)]
       localError(c.config, n.info, errGenerated, err)
       return newOrPrevType(tyError, prev, c)