diff --git a/util/build-win.sh b/util/build-win.sh
index 66a75c6fc..aa644f0c6 100755
--- a/util/build-win.sh
+++ b/util/build-win.sh
@@ -16,7 +16,10 @@ cd ..
 
 ./autogen.sh
 
-CONFIG_SITE=$PWD/depends/x86_64-w64-mingw32/share/config.site CXXFLAGS="-DPTW32_STATIC_LIB -DCURL_STATICLIB -fopenmp -pthread" ./configure --prefix="${PREFIX}" --host=x86_64-w64-mingw32 --enable-static --disable-shared
+# -Wa,-mbig-obj: the daemon's large template/boost-heavy TUs (e.g. asyncrpcoperation.cpp) exceed the
+# standard PE/COFF ~32k-section limit, which makes GNU ld emit "dangerous relocation" on .pdata and
+# crash. The bigobj COFF variant lifts that limit (same flag Bitcoin Core sets for the mingw host).
+CONFIG_SITE=$PWD/depends/x86_64-w64-mingw32/share/config.site CXXFLAGS="-DPTW32_STATIC_LIB -DCURL_STATICLIB -fopenmp -pthread -Wa,-mbig-obj" ./configure --prefix="${PREFIX}" --host=x86_64-w64-mingw32 --enable-static --disable-shared
 
 # Build CryptoConditions stuff
 WD=$PWD