diff --git a/dlls/jscript/compile.c b/dlls/jscript/compile.c
index 8431b5cf7d5..1bc887ca85d 100644
--- a/dlls/jscript/compile.c
+++ b/dlls/jscript/compile.c
@@ -115,6 +115,8 @@ static HRESULT compile_expression(compiler_ctx_t *ctx, expression_t *expr)
         return compile_unary_expression(ctx, (unary_expression_t*)expr, OP_neg);
     case EXPR_NOTEQEQ:
         return compile_binary_expression(ctx, (binary_expression_t*)expr, OP_neq2);
+    case EXPR_PLUS:
+        return compile_unary_expression(ctx, (unary_expression_t*)expr, OP_tonum);
     default:
         assert(expr->eval != compiled_expression_eval);
         return compile_interp_fallback(ctx, expr);
diff --git a/dlls/jscript/engine.c b/dlls/jscript/engine.c
index 17d8fa66bde..1f5863a9a02 100644
--- a/dlls/jscript/engine.c
+++ b/dlls/jscript/engine.c
@@ -2532,32 +2532,20 @@ HRESULT minus_expression_eval(script_ctx_t *ctx, expression_t *_expr, DWORD flag
 }
 
 /* ECMA-262 3rd Edition    11.4.6 */
-HRESULT plus_expression_eval(script_ctx_t *ctx, expression_t *_expr, DWORD flags, jsexcept_t *ei, exprval_t *ret)
+HRESULT interp_tonum(exec_ctx_t *ctx)
 {
-    unary_expression_t *expr = (unary_expression_t*)_expr;
-    exprval_t exprval;
-    VARIANT val, num;
+    VARIANT *v, num;
     HRESULT hres;
 
     TRACE("\n");
 
-    hres = expr_eval(ctx, expr->expression, EXPR_NEWREF, ei, &exprval);
+    v = stack_pop(ctx);
+    hres = to_number(ctx->parser->script, v, &ctx->ei, &num);
+    VariantClear(v);
     if(FAILED(hres))
         return hres;
 
-    hres = exprval_to_value(ctx, &exprval, ei, &val);
-    exprval_release(&exprval);
-    if(FAILED(hres))
-        return hres;
-
-    hres = to_number(ctx, &val, ei, &num);
-    VariantClear(&val);
-    if(FAILED(hres))
-        return hres;
-
-    ret->type = EXPRVAL_VARIANT;
-    ret->u.var = num;
-    return S_OK;
+    return stack_push(ctx, &num);
 }
 
 /* ECMA-262 3rd Edition    11.3.1 */
diff --git a/dlls/jscript/engine.h b/dlls/jscript/engine.h
index 8692b0ae567..c004af3097b 100644
--- a/dlls/jscript/engine.h
+++ b/dlls/jscript/engine.h
@@ -46,6 +46,7 @@ typedef struct _func_stack {
     X(eq2, 1, 0)                                  \
     X(neg, 1, 0)                                  \
     X(neq2, 1, 0)                                 \
+    X(tonum, 1, 0)                                \
     X(tree, 1, ARG_EXPR)                          \
     X(ret, 0, 0)
 
@@ -537,7 +538,6 @@ HRESULT delete_expression_eval(script_ctx_t*,expression_t*,DWORD,jsexcept_t*,exp
 HRESULT void_expression_eval(script_ctx_t*,expression_t*,DWORD,jsexcept_t*,exprval_t*) DECLSPEC_HIDDEN;
 HRESULT typeof_expression_eval(script_ctx_t*,expression_t*,DWORD,jsexcept_t*,exprval_t*) DECLSPEC_HIDDEN;
 HRESULT minus_expression_eval(script_ctx_t*,expression_t*,DWORD,jsexcept_t*,exprval_t*) DECLSPEC_HIDDEN;
-HRESULT plus_expression_eval(script_ctx_t*,expression_t*,DWORD,jsexcept_t*,exprval_t*) DECLSPEC_HIDDEN;
 HRESULT post_increment_expression_eval(script_ctx_t*,expression_t*,DWORD,jsexcept_t*,exprval_t*) DECLSPEC_HIDDEN;
 HRESULT post_decrement_expression_eval(script_ctx_t*,expression_t*,DWORD,jsexcept_t*,exprval_t*) DECLSPEC_HIDDEN;
 HRESULT pre_increment_expression_eval(script_ctx_t*,expression_t*,DWORD,jsexcept_t*,exprval_t*) DECLSPEC_HIDDEN;
diff --git a/dlls/jscript/parser.y b/dlls/jscript/parser.y
index d580ec0f0ca..92c79fcc2bd 100644
--- a/dlls/jscript/parser.y
+++ b/dlls/jscript/parser.y
@@ -1322,7 +1322,7 @@ static const expression_eval_t expression_eval_table[] = {
    void_expression_eval,
    typeof_expression_eval,
    minus_expression_eval,
-   plus_expression_eval,
+   compiled_expression_eval,
    post_increment_expression_eval,
    post_decrement_expression_eval,
    pre_increment_expression_eval,