diff --git a/.github/workflows/build-xserver.yml b/.github/workflows/build-xserver.yml
index 9154a67cd7..27af3b30d7 100644
--- a/.github/workflows/build-xserver.yml
+++ b/.github/workflows/build-xserver.yml
@@ -233,7 +233,7 @@ jobs:
         runs-on: ubuntu-latest
         env:
             MYTOKEN : ${{ secrets.MYTOKEN }}
-            MESON_ARGS: -Dprefix=/usr -Dxephyr=true -Dwerror=false -Dxcsecurity=true -Dxorg=true -Dxvfb=true -Dxnest=true -Dxfbdev=false
+            MESON_ARGS: -Dprefix=/usr -Dxephyr=true -Dwerror=true -Dxcsecurity=true -Dxorg=true -Dxvfb=true -Dxnest=true -Dxfbdev=false
         steps:
             - uses: actions/checkout@v4
             - name: run in freebsd VM
diff --git a/meson.build b/meson.build
index fb5e0b928e..4dbb4a7921 100644
--- a/meson.build
+++ b/meson.build
@@ -18,6 +18,12 @@ add_project_arguments('-fno-common', language: 'c')
 add_project_arguments('-Wshift-negative-value', language: 'c')
 add_project_arguments('-Wchar-subscripts', language: 'c')
 
+# workaround for mesa bug causing GLsync to be typedef'ed multiple times
+# this is breaking -Werror on FreeBSD
+if host_machine.system() == 'freebsd'
+    add_project_arguments('-Wno-error=typedef-redefinition', language: 'c')
+endif
+
 add_project_link_arguments('-fvisibility=hidden', language : 'c')
 
 # global config data -- needs to be declared early