fixes #23947; .uint8 compile-time error (#23948)

fixes #23947

compiler/vmgen.nim

@@ -2228,18 +2228,21 @@ proc gen(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags = {}) =
     #discard genProc(c, s)
     genLit(c, newSymNode(n[namePos].sym), dest)
   of nkChckRangeF, nkChckRange64, nkChckRange:
-    let
-      tmp0 = c.genx(n[0])
-      tmp1 = c.genx(n[1])
-      tmp2 = c.genx(n[2])
-    c.gABC(n, opcRangeChck, tmp0, tmp1, tmp2)
-    c.freeTemp(tmp1)
-    c.freeTemp(tmp2)
-    if dest >= 0:
-      gABC(c, n, whichAsgnOpc(n), dest, tmp0)
-      c.freeTemp(tmp0)
+    if skipTypes(n.typ, abstractVar).kind in {tyUInt..tyUInt64}:
+      genConv(c, n, n[0], dest)
     else:
-      dest = tmp0
+      let
+        tmp0 = c.genx(n[0])
+        tmp1 = c.genx(n[1])
+        tmp2 = c.genx(n[2])
+      c.gABC(n, opcRangeChck, tmp0, tmp1, tmp2)
+      c.freeTemp(tmp1)
+      c.freeTemp(tmp2)
+      if dest >= 0:
+        gABC(c, n, whichAsgnOpc(n), dest, tmp0)
+        c.freeTemp(tmp0)
+      else:
+        dest = tmp0
   of nkEmpty, nkCommentStmt, nkTypeSection, nkConstSection, nkPragma,
      nkTemplateDef, nkIncludeStmt, nkImportStmt, nkFromStmt, nkExportStmt,
      nkMixinStmt, nkBindStmt, declarativeDefs, nkMacroDef:

tests/int/t1.nim

@@ -17,6 +17,16 @@ doAssert typeOf(myInt16 + 2i32) is int32  # of type `int32`
 doAssert int32 isnot int64
 doAssert int32 isnot int
 
+block: # bug #23947
+  template foo =
+    let test_u64 : uint64 =   0xFF07.uint64
+    let test_u8  : uint8  = test_u64.uint8
+        # Error: illegal conversion from '65287' to '[0..255]'
+    doAssert test_u8 == 7
+
+  static: foo()
+  foo()
+
 block:
   # bug #22085
   const