wgl: Fix null pointer reference.

diff --git a/src/gallium/state_trackers/wgl/icd/stw_icd.c b/src/gallium/state_trackers/wgl/icd/stw_icd.c
index 5c78c19f926cacc37b6f0bfdb07388649c3fec90..8fa9f4e667f7027341495f5db730349440c2b714 100644 (file)
--- a/src/gallium/state_trackers/wgl/icd/stw_icd.c
+++ b/src/gallium/state_trackers/wgl/icd/stw_icd.c
@@ -89,6 +89,9 @@ lookup_context( DHGLRC dhglrc )
        dhglrc >= DRV_CONTEXT_MAX)
       return NULL;
 
+   if(!stw_icd)
+      return NULL;
+
    return stw_icd->ctx_array[dhglrc - 1].ctx;
 }