diff --git a/test/i420_video_source.h b/test/i420_video_source.h
index 0dc29319c..bcbe8a717 100644
--- a/test/i420_video_source.h
+++ b/test/i420_video_source.h
@@ -49,7 +49,7 @@ class I420VideoSource : public VideoSource {
     if (input_file_)
       fclose(input_file_);
     input_file_ = OpenTestDataFile(file_name_);
-    ASSERT_TRUE(input_file_) << "Input file open failed. Filename: "
+    ASSERT_TRUE(input_file_ != NULL) << "Input file open failed. Filename: "
         << file_name_;
     if (start_) {
       fseek(input_file_, raw_sz_ * start_, SEEK_SET);
@@ -92,6 +92,7 @@ class I420VideoSource : public VideoSource {
   }
 
   virtual void FillFrame() {
+    ASSERT_TRUE(input_file_ != NULL);
     // Read a frame from input_file.
     if (fread(img_->img_data, raw_sz_, 1, input_file_) == 0) {
       limit_ = frame_;
diff --git a/test/ivf_video_source.h b/test/ivf_video_source.h
index 48c3a7dcd..88bc597ae 100644
--- a/test/ivf_video_source.h
+++ b/test/ivf_video_source.h
@@ -52,7 +52,7 @@ class IVFVideoSource : public CompressedVideoSource {
 
   virtual void Begin() {
     input_file_ = OpenTestDataFile(file_name_);
-    ASSERT_TRUE(input_file_) << "Input file open failed. Filename: "
+    ASSERT_TRUE(input_file_ != NULL) << "Input file open failed. Filename: "
         << file_name_;
 
     // Read file header
@@ -72,6 +72,7 @@ class IVFVideoSource : public CompressedVideoSource {
   }
 
   void FillFrame() {
+    ASSERT_TRUE(input_file_ != NULL);
     uint8_t frame_hdr[kIvfFrameHdrSize];
     // Check frame header and read a frame from input_file.
     if (fread(frame_hdr, 1, kIvfFrameHdrSize, input_file_)
diff --git a/test/test_vector_test.cc b/test/test_vector_test.cc
index 481860e44..fe9c402f5 100644
--- a/test/test_vector_test.cc
+++ b/test/test_vector_test.cc
@@ -149,6 +149,7 @@ class TestVectorTest : public ::libvpx_test::DecoderTest,
 
   virtual void DecompressedFrameHook(const vpx_image_t& img,
                                      const unsigned int frame_number) {
+    ASSERT_TRUE(md5_file_ != NULL);
     char expected_md5[33];
     char junk[128];
 
diff --git a/test/webm_video_source.h b/test/webm_video_source.h
index c7919a979..9fc854593 100644
--- a/test/webm_video_source.h
+++ b/test/webm_video_source.h
@@ -99,7 +99,7 @@ class WebMVideoSource : public CompressedVideoSource {
 
   virtual void Begin() {
     input_file_ = OpenTestDataFile(file_name_);
-    ASSERT_TRUE(input_file_) << "Input file open failed. Filename: "
+    ASSERT_TRUE(input_file_ != NULL) << "Input file open failed. Filename: "
         << file_name_;
 
     nestegg_io io = {nestegg_read_cb, nestegg_seek_cb, nestegg_tell_cb,
@@ -130,6 +130,7 @@ class WebMVideoSource : public CompressedVideoSource {
   }
 
   void FillFrame() {
+    ASSERT_TRUE(input_file_ != NULL);
     if (chunk_ >= chunks_) {
       unsigned int track;