From 3a6df1dbe4ee9d92fb8f94bb6290b303bcc0bef1 Mon Sep 17 00:00:00 2001
From: Andrew Johnson <andrew.johnson@arjohnsonau.com>
Date: Mon, 3 Aug 2026 18:33:46 +0800
Subject: [PATCH] Add -mbig-obj flag for windows debug builds

---
 R/compiler-flags.R | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/R/compiler-flags.R b/R/compiler-flags.R
index 3d4f3cc..948e450 100644
--- a/R/compiler-flags.R
+++ b/R/compiler-flags.R
@@ -59,6 +59,19 @@ compiler_flags <- function(debug = FALSE) {
     )
     res[flags] <- paste(res[flags], "-fdiagnostics-color=always")
   }
+
+  if (debug && .Platform$OS.type == "windows") {
+    flags <- c(
+      "CFLAGS",
+      "CXXFLAGS",
+      "CXX11FLAGS",
+      "CXX14FLAGS",
+      "CXX17FLAGS",
+      "CXX20FLAGS"
+    )
+    # Debug symbols can generate too many sections on Windows
+    res[flags] <- paste(res[flags], "-Wa,-mbig-obj")
+  }
   res
 }