diff --git a/netwerk/cache/src/nsDiskCacheDevice.cpp b/netwerk/cache/src/nsDiskCacheDevice.cpp
index 5a6644a17a0..b09d8ed5d07 100644
--- a/netwerk/cache/src/nsDiskCacheDevice.cpp
+++ b/netwerk/cache/src/nsDiskCacheDevice.cpp
@@ -1510,7 +1510,8 @@ nsresult nsDiskCacheDevice::clobberDiskCache()
 }
 
 
-static int compareRecords(const void* e1, const void* e2, void* /*unused*/)
+PR_STATIC_CALLBACK(int)
+compareRecords(const void* e1, const void* e2, void* /*unused*/)
 {
     const nsDiskCacheRecord* r1 = (const nsDiskCacheRecord*) e1;
     const nsDiskCacheRecord* r2 = (const nsDiskCacheRecord*) e2;