diff --git a/src/gpu/gl/GrGLGpu.cpp b/src/gpu/gl/GrGLGpu.cpp
index ebda8ac62c..7a662899c6 100644
--- a/src/gpu/gl/GrGLGpu.cpp
+++ b/src/gpu/gl/GrGLGpu.cpp
@@ -2970,6 +2970,7 @@ static void get_gl_swizzle_values(const GrSwizzle& swizzle, GrGLenum glValues[4]
             case 'g': glValues[i] = GR_GL_GREEN; break;
             case 'b': glValues[i] = GR_GL_BLUE;  break;
             case 'a': glValues[i] = GR_GL_ALPHA; break;
+            case '1': glValues[i] = GR_GL_ONE;   break;
             default:  SK_ABORT("Unsupported component");
         }
     }