fixes some regressions

compiler/semtempl.nim

@@ -581,6 +581,11 @@ proc semPatternBody(c: var TemplCtx, n: PNode): PNode =
       localError(n.info, errInvalidExpression)
       result = n
 
+  proc stupidStmtListExpr(n: PNode): bool =
+    for i in 0 .. n.len-2:
+      if n[i].kind notin {nkEmpty, nkCommentStmt}: return false
+    result = true
+
   result = n
   case n.kind
   of nkIdent:
@@ -606,6 +611,12 @@ proc semPatternBody(c: var TemplCtx, n: PNode): PNode =
         localError(n.info, errInvalidExpression)
     else:
       localError(n.info, errInvalidExpression)
+  of nkStmtList, nkStmtListExpr:
+    if stupidStmtListExpr(n):
+      result = semPatternBody(c, n.lastSon)
+    else:
+      for i in countup(0, sonsLen(n) - 1):
+        result.sons[i] = semPatternBody(c, n.sons[i])
   of nkCallKinds:
     let s = qualifiedLookUp(c.c, n.sons[0], {})
     if s != nil:

compiler/vm.nim

@@ -1461,6 +1461,8 @@ proc evalConstExprAux(module, prc: PSym, n: PNode, mode: TEvalMode): PNode =
   let n = transformExpr(module, n)
   setupGlobalCtx(module)
   var c = globalCtx
+  let oldMode = c.mode
+  defer: c.mode = oldMode
   c.mode = mode
   let start = genExpr(c, n, requiresValue = mode!=emStaticStmt)
   if c.code[start].opcode == opcEof: return emptyNode