diff --git a/libs/gui/tests/Android.bp b/libs/gui/tests/Android.bp
index fa87f29..908959c 100644
--- a/libs/gui/tests/Android.bp
+++ b/libs/gui/tests/Android.bp
@@ -7,6 +7,10 @@
     test_suites: ["device-tests"],
 
     clang: true,
+    cflags: [
+        "-Wall",
+        "-Werror",
+    ],
 
     srcs: [
         "BufferItemConsumer_test.cpp",
diff --git a/libs/gui/tests/CpuConsumer_test.cpp b/libs/gui/tests/CpuConsumer_test.cpp
index 0982d7e..588e541 100644
--- a/libs/gui/tests/CpuConsumer_test.cpp
+++ b/libs/gui/tests/CpuConsumer_test.cpp
@@ -310,8 +310,6 @@
     uint32_t h = buf.height;
     const int blockWidth = w > 16 ? w / 16 : 1;
     const int blockHeight = h > 16 ? h / 16 : 1;
-    const int blockRows = h / blockHeight;
-    const int blockCols = w / blockWidth;
 
     // Top-left square is bright
     checkPixel(buf, 0, 0, 191);
@@ -349,8 +347,6 @@
     uint32_t h = buf.height;
     const int blockWidth = w > 16 ? w / 16 : 1;
     const int blockHeight = h > 16 ? h / 16 : 1;
-    const int blockRows = h / blockHeight;
-    const int blockCols = w / blockWidth;
 
     // Top-left square is bright red
     checkPixel(buf, 0, 0, 191, 63, 63);
@@ -392,8 +388,6 @@
     uint32_t h = buf.height;
     const int blockWidth = (w > 16 ? w / 8 : 2) & ~0x1;
     const int blockHeight = (h > 16 ? h / 8 : 2) & ~0x1;
-    const int blockRows = h / blockHeight;
-    const int blockCols = w / blockWidth;
 
     // Top-left square is red
     checkPixel(buf, 0, 0, 1000, 200, 200);
diff --git a/libs/gui/tests/SurfaceTextureGL_test.cpp b/libs/gui/tests/SurfaceTextureGL_test.cpp
index c6745d0..5639286 100644
--- a/libs/gui/tests/SurfaceTextureGL_test.cpp
+++ b/libs/gui/tests/SurfaceTextureGL_test.cpp
@@ -323,7 +323,6 @@
         for (int j = 0; j < numTestPixels; j++) {
             int x = testPixels[j].x;
             int y = testPixels[j].y;
-            uint8_t value = 0;
             if (j == (i % numTestPixels)) {
                 // We must y-invert the texture coords
                 EXPECT_TRUE(checkPixel(x, texHeight-y-1, 255, 255, 255, 255));
diff --git a/libs/gui/tests/Surface_test.cpp b/libs/gui/tests/Surface_test.cpp
index e18af17..e572e51 100644
--- a/libs/gui/tests/Surface_test.cpp
+++ b/libs/gui/tests/Surface_test.cpp
@@ -1075,7 +1075,6 @@
     EXPECT_EQ(initialCompositorTiming.presentLatency,
               compositeToPresentLatency);
 
-    const uint64_t fId1 = getNextFrameId();
     dequeueAndQueue(0);
     addFrameEvents(true, NO_FRAME_INDEX, 0);
 
@@ -1089,7 +1088,6 @@
     EXPECT_EQ(initialCompositorTiming.presentLatency,
               compositeToPresentLatency);
 
-    const uint64_t fId2 = getNextFrameId();
     dequeueAndQueue(1);
     addFrameEvents(true, 0, 1);
 
@@ -1162,7 +1160,6 @@
     nsecs_t expectedDeadline = initialCompositorTiming.deadline;
     EXPECT_EQ(expectedDeadline, compositeDeadline);
 
-    const uint64_t fId1 = getNextFrameId();
     dequeueAndQueue(0);
     addFrameEvents(true, NO_FRAME_INDEX, 0);
 
@@ -1175,7 +1172,6 @@
             initialCompositorTiming.deadline +initialCompositorTiming.interval;
     EXPECT_EQ(expectedDeadline, compositeDeadline);
 
-    const uint64_t fId2 = getNextFrameId();
     dequeueAndQueue(1);
     addFrameEvents(true, 0, 1);