diff --git a/opengl/tests/hwc/hwcCommit.cpp b/opengl/tests/hwc/hwcCommit.cpp
index 3686dab..0a6ff55 100644
--- a/opengl/tests/hwc/hwcCommit.cpp
+++ b/opengl/tests/hwc/hwcCommit.cpp
@@ -183,7 +183,7 @@
     uint32_t lower(void) { return _l; }
     uint32_t upper(void) { return _u; }
 
-    operator string();
+    operator string(); // NOLINT(google-explicit-constructor)
 
 private:
     uint32_t _l; // lower
@@ -216,7 +216,9 @@
     static void double2Rational(double f, Range nRange, Range dRange,
                                Rational& lower, Rational& upper);
         
+    // NOLINTNEXTLINE(google-explicit-constructor)
     operator string() const;
+    // NOLINTNEXTLINE(google-explicit-constructor)
     operator double() const { return (double) _n / (double) _d; }
 
 
diff --git a/opengl/tests/hwc/hwcTestLib.h b/opengl/tests/hwc/hwcTestLib.h
index 922fc19..5a49393 100644
--- a/opengl/tests/hwc/hwcTestLib.h
+++ b/opengl/tests/hwc/hwcTestLib.h
@@ -58,7 +58,7 @@
     float c2(void) const { return _c2; }
     float c3(void) const { return _c3; }
 
-    operator std::string();
+    operator std::string(); // NOLINT(google-explicit-constructor)
 
   private:
     float _c1;
@@ -71,7 +71,7 @@
 class ColorRGB {
   public:
     ColorRGB(): _r(0.0), _g(0.0), _b(0.0) {};
-    ColorRGB(float f): _r(f), _g(f), _b(f) {}; // Gray, NOLINT(implicit)
+    ColorRGB(float f): _r(f), _g(f), _b(f) {}; // Gray, NOLINT(google-explicit-constructor)
     ColorRGB(float r, float g, float b): _r(r), _g(g), _b(b) {};
     float r(void) const { return _r; }
     float g(void) const { return _g; }
@@ -93,8 +93,8 @@
     void setWidth(uint32_t w) { _w = w; }
     void setHeight(uint32_t h) { _h = h; }
 
-    operator std::string();
-    operator hwc_rect() const;
+    operator std::string(); // NOLINT(google-explicit-constructor)
+    operator hwc_rect() const; // NOLINT(google-explicit-constructor)
 
   private:
     uint32_t _w;