Index: clang/lib/Sema/SemaInit.cpp
===================================================================
--- clang/lib/Sema/SemaInit.cpp
+++ clang/lib/Sema/SemaInit.cpp
@@ -8248,7 +8248,7 @@
       // argument passing.
       assert(Step->Type->isSamplerT() &&
              "Sampler initialization on non-sampler type.");
-      Expr *Init = CurInit.get();
+      Expr *Init = CurInit.get()->IgnoreParens();
       QualType SourceType = Init->getType();
       // Case 1
       if (Entity.isParameterKind()) {
Index: clang/test/SemaOpenCL/sampler_t.cl
===================================================================
--- clang/test/SemaOpenCL/sampler_t.cl
+++ clang/test/SemaOpenCL/sampler_t.cl
@@ -10,6 +10,9 @@
 #define CLK_FILTER_NEAREST              0x10
 #define CLK_FILTER_LINEAR               0x20
 
+typedef float float4 __attribute__((ext_vector_type(4)));
+float4 read_imagef(read_only image1d_t, sampler_t, float);
+
 constant sampler_t glb_smp = CLK_ADDRESS_CLAMP_TO_EDGE | CLK_NORMALIZED_COORDS_TRUE | CLK_FILTER_LINEAR;
 constant sampler_t glb_smp2; // expected-error{{variable in constant address space must be initialized}}
 global sampler_t glb_smp3 = CLK_ADDRESS_CLAMP_TO_EDGE | CLK_NORMALIZED_COORDS_TRUE | CLK_FILTER_NEAREST; // expected-error{{sampler type cannot be used with the __local and __global address space qualifiers}} expected-error {{global sampler requires a const or constant address space qualifier}}
@@ -74,3 +77,7 @@
   foo(smp1+1); //expected-error{{invalid operands to binary expression ('sampler_t' and 'int')}}
 }
 
+void smp_args(read_only image1d_t image) {
+  // Test that parentheses around sampler arguments are ignored.
+  float4 res = read_imagef(image, (glb_smp10), 0.0f);
+}