diff --git a/bench/ColorPrivBench.cpp b/bench/ColorPrivBench.cpp
index 23cc48f3cc..a19dc5e2a3 100644
--- a/bench/ColorPrivBench.cpp
+++ b/bench/ColorPrivBench.cpp
@@ -41,7 +41,7 @@ public:
 
     void onDraw(int loops, SkCanvas*) override {
         // We xor results of FourByteInterp into junk to make sure the function runs.
-        SK_MAYBE_UNUSED volatile SkPMColor junk = 0;
+        [[maybe_unused]] volatile SkPMColor junk = 0;
 
         for (int loop = 0; loop < loops; loop++) {
             for (int i = 0; i < kInputs; i++) {
diff --git a/bench/ControlBench.cpp b/bench/ControlBench.cpp
index 19696934ab..5794bfe3e3 100644
--- a/bench/ControlBench.cpp
+++ b/bench/ControlBench.cpp
@@ -16,7 +16,7 @@ struct ControlBench : public Benchmark {
 
     void onDraw(int loops, SkCanvas*) override {
         // Nothing terribly useful: force a memory read, a memory write, and some math.
-        SK_MAYBE_UNUSED volatile uint32_t rand = 0;
+        [[maybe_unused]] volatile uint32_t rand = 0;
         for (int i = 0; i < 1000*loops; i++) {
             rand *= 1664525;
             rand += 1013904223;
diff --git a/bench/MatrixBench.cpp b/bench/MatrixBench.cpp
index 07683ead7e..b19daa4a8a 100644
--- a/bench/MatrixBench.cpp
+++ b/bench/MatrixBench.cpp
@@ -53,7 +53,7 @@ protected:
         m2.reset();
 
         // xor into a volatile prevents these comparisons from being optimized away.
-        SK_MAYBE_UNUSED volatile bool junk = false;
+        [[maybe_unused]] volatile bool junk = false;
         junk ^= (m0 == m1);
         junk ^= (m1 == m2);
         junk ^= (m2 == m0);
@@ -116,7 +116,7 @@ protected:
                        fArray[3], fArray[4], fArray[5],
                        fArray[6], fArray[7], fArray[8]);
         // xoring into a volatile prevents the compiler from optimizing these away
-        SK_MAYBE_UNUSED volatile int junk = 0;
+        [[maybe_unused]] volatile int junk = 0;
         junk ^= (fMatrix.getType());
         fMatrix.dirtyMatrixTypeCache();
         junk ^= (fMatrix.getType());
diff --git a/bench/ScalarBench.cpp b/bench/ScalarBench.cpp
index e47fc63aee..80e96afb2d 100644
--- a/bench/ScalarBench.cpp
+++ b/bench/ScalarBench.cpp
@@ -59,7 +59,7 @@ protected:
     int mulLoopCount() const override { return 4; }
     void performTest() override {
         // xoring into a volatile prevents the compiler from optimizing these checks away.
-        SK_MAYBE_UNUSED volatile bool junk = false;
+        [[maybe_unused]] volatile bool junk = false;
         junk ^= (fArray[6] != 0.0f || fArray[7] != 0.0f || fArray[8] != 1.0f);
         junk ^= (fArray[2] != 0.0f || fArray[5] != 0.0f);
     }
@@ -78,7 +78,7 @@ protected:
     int mulLoopCount() const override { return 4; }
     void performTest() override {
         // xoring into a volatile prevents the compiler from optimizing these checks away.
-        SK_MAYBE_UNUSED volatile int32_t junk = 0;
+        [[maybe_unused]] volatile int32_t junk = 0;
         junk ^= (SkScalarAs2sCompliment(fArray[6]) |
                  SkScalarAs2sCompliment(fArray[7]) |
                 (SkScalarAs2sCompliment(fArray[8]) - kPersp1Int));
diff --git a/bench/TessellateBench.cpp b/bench/TessellateBench.cpp
index 21cd6fec9b..9dd2524591 100644
--- a/bench/TessellateBench.cpp
+++ b/bench/TessellateBench.cpp
@@ -63,7 +63,7 @@ static SkPath make_conic_path() {
     return path;
 }
 
-SK_MAYBE_UNUSED static SkPath make_quad_path(int maxPow2) {
+[[maybe_unused]] static SkPath make_quad_path(int maxPow2) {
     SkRandom rand;
     SkPath path;
     for (int i = 0; i < kNumCubicsInChalkboard; ++i) {
@@ -73,7 +73,7 @@ SK_MAYBE_UNUSED static SkPath make_quad_path(int maxPow2) {
     return path;
 }
 
-SK_MAYBE_UNUSED static SkPath make_line_path(int maxPow2) {
+[[maybe_unused]] static SkPath make_line_path(int maxPow2) {
     SkRandom rand;
     SkPath path;
     for (int i = 0; i < kNumCubicsInChalkboard; ++i) {
diff --git a/gm/rasterhandleallocator.cpp b/gm/rasterhandleallocator.cpp
index fa4488bb3a..e2e889a486 100644
--- a/gm/rasterhandleallocator.cpp
+++ b/gm/rasterhandleallocator.cpp
@@ -255,7 +255,7 @@ public:
 
         RECT clip_bounds_RECT = toRECT(clip_bounds);
         HRGN hrgn = CreateRectRgnIndirect(&clip_bounds_RECT);
-        SK_MAYBE_UNUSED int result = SelectClipRgn(hdc, hrgn);
+        [[maybe_unused]] int result = SelectClipRgn(hdc, hrgn);
         SkASSERT(result != ERROR);
         result = DeleteObject(hrgn);
         SkASSERT(result != 0);
diff --git a/include/core/SkTypes.h b/include/core/SkTypes.h
index 8adaf3ac09..47274c5106 100644
--- a/include/core/SkTypes.h
+++ b/include/core/SkTypes.h
@@ -340,14 +340,6 @@
 #  endif
 #endif
 
-#if !defined(SK_MAYBE_UNUSED)
-#  if defined(__clang__) || defined(__GNUC__)
-#    define SK_MAYBE_UNUSED [[maybe_unused]]
-#  else
-#    define SK_MAYBE_UNUSED
-#  endif
-#endif
-
 /**
  * If your judgment is better than the compiler's (i.e. you've profiled it),
  * you can use SK_ALWAYS_INLINE to force inlining. E.g.
diff --git a/include/gpu/GrTypes.h b/include/gpu/GrTypes.h
index 20fc62f699..f8895345d6 100644
--- a/include/gpu/GrTypes.h
+++ b/include/gpu/GrTypes.h
@@ -36,37 +36,37 @@ private:
  * basic bitfield.
  */
 #define GR_MAKE_BITFIELD_CLASS_OPS(X) \
-    SK_MAYBE_UNUSED constexpr GrTFlagsMask<X> operator~(X a) { \
+    [[maybe_unused]] constexpr GrTFlagsMask<X> operator~(X a) { \
         return GrTFlagsMask<X>(~static_cast<int>(a)); \
     } \
-    SK_MAYBE_UNUSED constexpr X operator|(X a, X b) { \
+    [[maybe_unused]] constexpr X operator|(X a, X b) { \
         return static_cast<X>(static_cast<int>(a) | static_cast<int>(b)); \
     } \
-    SK_MAYBE_UNUSED inline X& operator|=(X& a, X b) { \
+    [[maybe_unused]] inline X& operator|=(X& a, X b) { \
         return (a = a | b); \
     } \
-    SK_MAYBE_UNUSED constexpr bool operator&(X a, X b) { \
+    [[maybe_unused]] constexpr bool operator&(X a, X b) { \
         return SkToBool(static_cast<int>(a) & static_cast<int>(b)); \
     } \
-    SK_MAYBE_UNUSED constexpr GrTFlagsMask<X> operator|(GrTFlagsMask<X> a, GrTFlagsMask<X> b) { \
+    [[maybe_unused]] constexpr GrTFlagsMask<X> operator|(GrTFlagsMask<X> a, GrTFlagsMask<X> b) { \
         return GrTFlagsMask<X>(a.value() | b.value()); \
     } \
-    SK_MAYBE_UNUSED constexpr GrTFlagsMask<X> operator|(GrTFlagsMask<X> a, X b) { \
+    [[maybe_unused]] constexpr GrTFlagsMask<X> operator|(GrTFlagsMask<X> a, X b) { \
         return GrTFlagsMask<X>(a.value() | static_cast<int>(b)); \
     } \
-    SK_MAYBE_UNUSED constexpr GrTFlagsMask<X> operator|(X a, GrTFlagsMask<X> b) { \
+    [[maybe_unused]] constexpr GrTFlagsMask<X> operator|(X a, GrTFlagsMask<X> b) { \
         return GrTFlagsMask<X>(static_cast<int>(a) | b.value()); \
     } \
-    SK_MAYBE_UNUSED constexpr X operator&(GrTFlagsMask<X> a, GrTFlagsMask<X> b) { \
+    [[maybe_unused]] constexpr X operator&(GrTFlagsMask<X> a, GrTFlagsMask<X> b) { \
         return static_cast<X>(a.value() & b.value()); \
     } \
-    SK_MAYBE_UNUSED constexpr X operator&(GrTFlagsMask<X> a, X b) { \
+    [[maybe_unused]] constexpr X operator&(GrTFlagsMask<X> a, X b) { \
         return static_cast<X>(a.value() & static_cast<int>(b)); \
     } \
-    SK_MAYBE_UNUSED constexpr X operator&(X a, GrTFlagsMask<X> b) { \
+    [[maybe_unused]] constexpr X operator&(X a, GrTFlagsMask<X> b) { \
         return static_cast<X>(static_cast<int>(a) & b.value()); \
     } \
-    SK_MAYBE_UNUSED inline X& operator&=(X& a, GrTFlagsMask<X> b) { \
+    [[maybe_unused]] inline X& operator&=(X& a, GrTFlagsMask<X> b) { \
         return (a = a & b); \
     } \
 
diff --git a/src/core/SkEnumBitMask.h b/src/core/SkEnumBitMask.h
index 3fe3bd5c8e..a04f6cd0b8 100644
--- a/src/core/SkEnumBitMask.h
+++ b/src/core/SkEnumBitMask.h
@@ -65,16 +65,16 @@ private:
  * Defines functions that make it possible to use bitwise operators on an enum.
  */
 #define SK_MAKE_BITMASK_OPS(E) \
-    SK_MAYBE_UNUSED constexpr SkEnumBitMask<E> operator|(E a, E b) { \
+    [[maybe_unused]] constexpr SkEnumBitMask<E> operator|(E a, E b) { \
         return SkEnumBitMask<E>(a) | b; \
     } \
-    SK_MAYBE_UNUSED constexpr SkEnumBitMask<E> operator&(E a, E b) { \
+    [[maybe_unused]] constexpr SkEnumBitMask<E> operator&(E a, E b) { \
         return SkEnumBitMask<E>(a) & b; \
     } \
-    SK_MAYBE_UNUSED constexpr SkEnumBitMask<E> operator^(E a, E b) { \
+    [[maybe_unused]] constexpr SkEnumBitMask<E> operator^(E a, E b) { \
         return SkEnumBitMask<E>(a) ^ b; \
     } \
-    SK_MAYBE_UNUSED constexpr SkEnumBitMask<E> operator~(E e) { \
+    [[maybe_unused]] constexpr SkEnumBitMask<E> operator~(E e) { \
         return ~SkEnumBitMask<E>(e); \
     } \
 
diff --git a/src/gpu/BufferWriter.h b/src/gpu/BufferWriter.h
index b93273e97a..35ad787c3f 100644
--- a/src/gpu/BufferWriter.h
+++ b/src/gpu/BufferWriter.h
@@ -304,7 +304,7 @@ inline VertexWriter& operator<<(VertexWriter& w, const VertexWriter::RepeatDesc<
 }
 
 template <>
-SK_MAYBE_UNUSED inline VertexWriter& operator<<(VertexWriter& w, const skvx::float4& vector) {
+[[maybe_unused]] inline VertexWriter& operator<<(VertexWriter& w, const skvx::float4& vector) {
     w.validate(sizeof(vector));
     vector.store(w.fPtr);
     w = w.makeOffset(sizeof(vector));
@@ -354,7 +354,7 @@ private:
 };
 
 template <>
-SK_MAYBE_UNUSED inline VertexWriter& operator<<(VertexWriter& w, const VertexColor& color) {
+[[maybe_unused]] inline VertexWriter& operator<<(VertexWriter& w, const VertexColor& color) {
     w << color.fColor[0];
     if (color.fWideColor) {
         w << color.fColor[1]
diff --git a/src/gpu/tessellate/Tessellation.h b/src/gpu/tessellate/Tessellation.h
index 8cb33d5b68..494622bcea 100644
--- a/src/gpu/tessellate/Tessellation.h
+++ b/src/gpu/tessellate/Tessellation.h
@@ -87,9 +87,9 @@ GR_MAKE_BITFIELD_CLASS_OPS(PatchAttribs)
 
 // When PatchAttribs::kExplicitCurveType is set, these are the values that tell the GPU what type of
 // curve is being drawn.
-constexpr static float kCubicCurveType SK_MAYBE_UNUSED = 0;
-constexpr static float kConicCurveType SK_MAYBE_UNUSED = 1;
-constexpr static float kTriangularConicCurveType SK_MAYBE_UNUSED = 2;  // Conic curve with w=Inf.
+constexpr static float kCubicCurveType [[maybe_unused]] = 0;
+constexpr static float kConicCurveType [[maybe_unused]] = 1;
+constexpr static float kTriangularConicCurveType [[maybe_unused]] = 2;  // Conic curve with w=Inf.
 
 // Returns the packed size in bytes of the attribs portion of tessellation patches (or instances) in
 // GPU buffers.
diff --git a/src/gpu/tessellate/WangsFormula.h b/src/gpu/tessellate/WangsFormula.h
index b8637b0f3f..73bdbff5a6 100644
--- a/src/gpu/tessellate/WangsFormula.h
+++ b/src/gpu/tessellate/WangsFormula.h
@@ -15,7 +15,7 @@
 #include "include/private/SkVx.h"
 #include "src/gpu/tessellate/Tessellation.h"
 
-#define AI SK_MAYBE_UNUSED SK_ALWAYS_INLINE
+#define AI [[maybe_unused]] SK_ALWAYS_INLINE
 
 // Wang's formula gives the minimum number of evenly spaced (in the parametric sense) line segments
 // that a bezier curve must be chopped into in order to guarantee all lines stay within a distance
diff --git a/src/shaders/SkImageShader.cpp b/src/shaders/SkImageShader.cpp
index 49f9800c0c..fc9487ec2e 100755
--- a/src/shaders/SkImageShader.cpp
+++ b/src/shaders/SkImageShader.cpp
@@ -79,7 +79,7 @@ static SkTileMode optimize(SkTileMode tm, int dimension) {
 // TODO: currently this only *always* used in asFragmentProcessor(), which is excluded on no-gpu
 // builds. No-gpu builds only use needs_subset() in asserts, so release+no-gpu doesn't use it, which
 // can cause builds to fail if unused warnings are treated as errors.
-SK_MAYBE_UNUSED static bool needs_subset(SkImage* img, const SkRect& subset) {
+[[maybe_unused]] static bool needs_subset(SkImage* img, const SkRect& subset) {
     return subset != SkRect::Make(img->dimensions());
 }