From fb8da16a60e13b09c5c6bb4989c204da536597b7 Mon Sep 17 00:00:00 2001
From: Andrew Kelley <andrew@ziglang.org>
Date: Mon, 13 Jan 2020 12:16:35 -0500
Subject: [PATCH] fix regressions in get_elem_ptr related to undefined

---
 src/ir.cpp                         | 8 ++++----
 test/stage1/behavior.zig           | 4 ++--
 test/stage1/behavior/undefined.zig | 5 +++--
 3 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/src/ir.cpp b/src/ir.cpp
index 8d3b98435a..e820616702 100644
--- a/src/ir.cpp
+++ b/src/ir.cpp
@@ -17918,6 +17918,9 @@ static IrInstruction *ir_get_var_ptr(IrAnalyze *ira, IrInstruction *instruction,
         var = var->next_var;
     }
 
+    if (var->var_type == nullptr || type_is_invalid(var->var_type))
+        return ira->codegen->invalid_instruction;
+
     bool is_volatile = false;
     ZigType *var_ptr_type = get_pointer_to_type_extra(ira->codegen, var->var_type,
             var->src_is_const, is_volatile, PtrLenSingle, var->align_bytes, 0, 0, false);
@@ -17926,9 +17929,6 @@ static IrInstruction *ir_get_var_ptr(IrAnalyze *ira, IrInstruction *instruction,
         return ir_implicit_cast(ira, var->ptr_instruction, var_ptr_type);
     }
 
-    if (var->var_type == nullptr || type_is_invalid(var->var_type))
-        return ira->codegen->invalid_instruction;
-
     ZigValue *mem_slot = nullptr;
 
     bool comptime_var_mem = ir_get_var_is_comptime(var);
@@ -19761,7 +19761,7 @@ static IrInstruction *ir_analyze_instruction_elem_ptr(IrAnalyze *ira, IrInstruct
                     array_ptr_val->data.x_ptr.special != ConstPtrSpecialHardCodedAddr))
             {
                 if ((err = ir_resolve_const_val(ira->codegen, ira->new_irb.exec,
-                    elem_ptr_instruction->base.source_node, array_ptr_val, UndefBad)))
+                    elem_ptr_instruction->base.source_node, array_ptr_val, UndefOk)))
                 {
                     return ira->codegen->invalid_instruction;
                 }
diff --git a/test/stage1/behavior.zig b/test/stage1/behavior.zig
index a468030f6b..bd091c0c60 100644
--- a/test/stage1/behavior.zig
+++ b/test/stage1/behavior.zig
@@ -66,7 +66,7 @@ comptime {
     _ = @import("behavior/fn.zig");
     _ = @import("behavior/fn_in_struct_in_comptime.zig");
     _ = @import("behavior/fn_delegation.zig");
-    //_ = @import("behavior/for.zig");
+    _ = @import("behavior/for.zig");
     _ = @import("behavior/generics.zig");
     _ = @import("behavior/hasdecl.zig");
     _ = @import("behavior/hasfield.zig");
@@ -107,7 +107,7 @@ comptime {
     _ = @import("behavior/type.zig");
     _ = @import("behavior/type_info.zig");
     _ = @import("behavior/typename.zig");
-    //_ = @import("behavior/undefined.zig");
+    _ = @import("behavior/undefined.zig");
     _ = @import("behavior/underscore.zig");
     _ = @import("behavior/union.zig");
     _ = @import("behavior/usingnamespace.zig");
diff --git a/test/stage1/behavior/undefined.zig b/test/stage1/behavior/undefined.zig
index 3506e7e240..114b0262b1 100644
--- a/test/stage1/behavior/undefined.zig
+++ b/test/stage1/behavior/undefined.zig
@@ -1,5 +1,6 @@
-const expect = @import("std").testing.expect;
-const mem = @import("std").mem;
+const std = @import("std");
+const expect = std.testing.expect;
+const mem = std.mem;
 
 fn initStaticArray() [10]i32 {
     var array: [10]i32 = undefined;