From 97f2a8b5cb4c882e05add16a69c7a55f7fe46794 Mon Sep 17 00:00:00 2001
From: Andrew Kelley <andrew@ziglang.org>
Date: Mon, 26 Feb 2024 23:48:56 -0700
Subject: [PATCH] introduce ZIG_DEBUG_CMD to choose debug mode

for lazily built commands such as `zig fmt` and `zig reduce`. Useful if
you want to test a patch to them.
---
 src/introspect.zig | 1 +
 src/main.zig       | 8 ++++++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/introspect.zig b/src/introspect.zig
index 765e9409ed..36821592df 100644
--- a/src/introspect.zig
+++ b/src/introspect.zig
@@ -153,6 +153,7 @@ pub const EnvVar = enum {
     ZIG_VERBOSE_LINK,
     ZIG_VERBOSE_CC,
     ZIG_BTRFS_WORKAROUND,
+    ZIG_DEBUG_CMD,
     CC,
     NO_COLOR,
     XDG_CACHE_HOME,
diff --git a/src/main.zig b/src/main.zig
index 65632cd16a..24ca355238 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -5735,6 +5735,10 @@ fn jitCmd(
         fatal("unable to find self exe path: {s}", .{@errorName(err)});
     };
 
+    const optimize_mode: std.builtin.OptimizeMode = if (EnvVar.ZIG_DEBUG_CMD.isSet())
+        .Debug
+    else
+        .ReleaseFast;
     const override_lib_dir: ?[]const u8 = try EnvVar.ZIG_LIB_DIR.get(arena);
     const override_global_cache_dir: ?[]const u8 = try EnvVar.ZIG_GLOBAL_CACHE_DIR.get(arena);
 
@@ -5777,7 +5781,7 @@ fn jitCmd(
 
         const config = try Compilation.Config.resolve(.{
             .output_mode = .Exe,
-            .root_optimize_mode = .ReleaseFast,
+            .root_optimize_mode = optimize_mode,
             .resolved_target = resolved_target,
             .have_zcu = true,
             .emit_bin = true,
@@ -5791,7 +5795,7 @@ fn jitCmd(
             .cc_argv = &.{},
             .inherited = .{
                 .resolved_target = resolved_target,
-                .optimize_mode = .ReleaseFast,
+                .optimize_mode = optimize_mode,
             },
             .global = config,
             .parent = null,