From 9ba89394df62b8b080d667075e3a592c5a9594a5 Mon Sep 17 00:00:00 2001
From: Matthew Lugg <mlugg@mlugg.co.uk>
Date: Sat, 25 Apr 2026 19:19:04 +0100
Subject: [PATCH] compiler: raise FD limit before opening link inputs

---
 src/main.zig | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/main.zig b/src/main.zig
index 817e8d29dc203b30a230c2ea3c3c2acb9958743d..95ee9a82f15ac3b6591fe07bc061dd9c336b1f4e 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -977,6 +977,11 @@ fn buildOutputType(
     var cc_argv: std.ArrayList([]const u8) = .empty;
     var deps: std.ArrayList(CliModule.Dep) = .empty;
 
+    // We need to raise the FD limit *before* CLI parsing, because we open link inputs during CLI
+    // parsing (in `createModule`), so a large number of link inputs could push us past the limit on
+    // targets with a low soft limit (e.g. macOS has a default limit of 256).
+    process.raiseFileDescriptorLimit();
+
     // Contains every module specified via -M. The dependencies are added
     // after argument parsing is completed. We use a StringArrayHashMap to make
     // error output consistent. "root" is special.
@@ -3534,8 +3539,6 @@ fn buildOutputType(
         break :b .whole;
     };
 
-    process.raiseFileDescriptorLimit();
-
     var file_system_inputs: std.ArrayList(u8) = .empty;
     defer file_system_inputs.deinit(gpa);
 
-- 
2.54.0