From 26539a087f7e0ff95c82e6fcd16f0017f4243e7e Mon Sep 17 00:00:00 2001
From: Brian McKenna <brian@brianmckenna.org>
Date: Fri, 31 Jan 2025 22:52:57 +1100
Subject: [PATCH] Add mbig-obj flag to allow cross-compiling libexpr to mingw32

---
 nix-meson-build-support/big-objs/meson.build | 4 ++++
 src/libexpr/meson.build                      | 1 +
 2 files changed, 5 insertions(+)
 create mode 100644 nix-meson-build-support/big-objs/meson.build

diff --git a/nix-meson-build-support/big-objs/meson.build b/nix-meson-build-support/big-objs/meson.build
new file mode 100644
index 000000000..f5abd8bd8
--- /dev/null
+++ b/nix-meson-build-support/big-objs/meson.build
@@ -0,0 +1,4 @@
+# libexpr's primops creates a large object
+# Without the following flag, we'll get errors when cross-compiling to mingw32:
+# Fatal error: can't write 66 bytes to section .text of src/libexpr/libnixexpr.dll.p/primops.cc.obj: 'file too big'
+add_project_arguments([ '-Wa,-mbig-obj' ], language: 'cpp')
diff --git a/src/libexpr/meson.build b/src/libexpr/meson.build
index b33aebc86..987300d58 100644
--- a/src/libexpr/meson.build
+++ b/src/libexpr/meson.build
@@ -24,6 +24,7 @@ deps_public_maybe_subproject = [
   dependency('nix-fetchers'),
 ]
 subdir('nix-meson-build-support/subprojects')
+subdir('nix-meson-build-support/big-objs')
 
 boost = dependency(
   'boost',