From 0e7523c7d7eb42a5927be4de897ab623f033d2fe Mon Sep 17 00:00:00 2001
From: Andrew Kelley <andrew@ziglang.org>
Date: Sat, 3 Oct 2020 17:16:19 -0700
Subject: [PATCH] stage1 main(): catch unreachable in debug builds for easier
 troubleshooting

Fixup to 2a3393eff853fe0a1dee766c859a345186e91fa3
---
 src/stage1.zig | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/src/stage1.zig b/src/stage1.zig
index 10b85899c2..f26622ee89 100644
--- a/src/stage1.zig
+++ b/src/stage1.zig
@@ -39,12 +39,11 @@ pub export fn main(argc: c_int, argv: [*]const [*:0]const u8) c_int {
     for (args) |*arg, i| {
         arg.* = mem.spanZ(argv[i]);
     }
-    stage2.mainArgs(gpa, arena, args) catch |err| {
-        if (@errorReturnTrace()) |trace| {
-            std.debug.dumpStackTrace(trace.*);
-        }
-        fatal("unhandled internal error: {}", .{@errorName(err)});
-    };
+    if (std.builtin.mode == .Debug) {
+        stage2.mainArgs(gpa, arena, args) catch unreachable;
+    } else {
+        stage2.mainArgs(gpa, arena, args) catch |err| fatal("{}", .{@errorName(err)});
+    }
     return 0;
 }