fixes #14126 [backport:1.2] (#14390)

* fixes #14126 [backport:1.2]

* used more logic to optimize it further; updated Nimble version

tests/ccgbugs/tcodegenbug1.nim

@@ -3,7 +3,10 @@ discard """
 obj.inner.id = 7
 id = 7
 obj = (inner: (kind: Just, id: 7))
-2'''
+2
+(a: "1", b: "2", c: "3")
+caught
+(a: "1", b: "", c: "3")'''
 """
 
 # bug #6960
@@ -129,12 +132,51 @@ import macros
 func myfunc(obj: MyObject): MyResult {.raises: [].} =
   template index: auto =
     case obj.kind:
-      of Float: $obj.index 
+      of Float: $obj.index
       of Fixed: "Fixed"
   macro to_str(a: untyped): string =
-    result = newStrLitNode(a.repr)  
+    result = newStrLitNode(a.repr)
   result.val[0] = index
   result.val[1] = to_str(obj.kind + Ola)
 
 let x = MyObject(someInt: 10, kind: Fixed)
 echo myfunc(x).val.len
+
+# bug #14126
+
+type X = object
+  a, b, c: string
+
+proc f(): X =
+  result.a = "a"
+  result.b = "b"
+  raise (ref ValueError)()
+
+proc ohmanNoNRVO =
+  var x: X
+  x.a = "1"
+  x.b = "2"
+  x.c = "3"
+
+  try:
+    x = f()
+  except:
+    discard
+
+  echo x
+  doAssert x.c == "3", "shouldn't modify x if f raises"
+
+ohmanNoNRVO()
+
+proc ohmanNoNRVO2(x: var X) =
+  x.a = "1"
+  x.c = "3"
+  x = f()
+
+var xgg: X
+try:
+  ohmanNoNRVO2(xgg)
+except:
+  echo "caught"
+echo xgg
+doAssert xgg.c == "3", "this assert will fail"