Fix for `ConstantBuffer<T[...]>` causing a segfault (#4705)

Fixes: #4704

Change the type we assign when getting the member variable of a legalized `ConstantBuffer<T[...]>`.

2 files changed, 19 insertions, 1 deletions

diff --git a/source/slang/slang-ir-lower-buffer-element-type.cpp b/source/slang/slang-ir-lower-buffer-element-type.cpp
index d042aae43..5eefc121e 100644
--- a/source/slang/slang-ir-lower-buffer-element-type.cpp
+++ b/source/slang/slang-ir-lower-buffer-element-type.cpp
@@ -703,7 +703,7 @@ namespace Slang
                                         for (UInt i = 0; i < user->getOperandCount(); i++)
                                             args.add(user->getOperand(i));
                                         auto newArrayPtrVal = builder.emitFieldAddress(
-                                            getLoweredPtrLikeType(ptrVal->getDataType(), loweredElementTypeInfo.loweredInnerArrayType),
+                                            builder.getPtrType(loweredElementTypeInfo.loweredInnerArrayType),
                                             ptrVal,
                                             loweredElementTypeInfo.loweredInnerStructKey);
                                         builder.replaceOperand(use, newArrayPtrVal);
diff --git a/tests/bugs/gh-4704.slang b/tests/bugs/gh-4704.slang
new file mode 100644
index 000000000..8e8f6fc36
--- /dev/null
+++ b/tests/bugs/gh-4704.slang
@@ -0,0 +1,18 @@
+//TEST:SIMPLE(filecheck=SPIRV): -entry computeMain -stage compute -target spirv
+//TEST:SIMPLE(filecheck=HLSL): -entry computeMain -stage compute -target spirv
+//TEST:SIMPLE(filecheck=GLSL): -entry computeMain -stage compute -target spirv
+
+// SPIRV: OpEntryPoint
+// GLSL: main
+// HLSL: computeMain
+
+
+[[vk::binding(0, 0)]] uniform ConstantBuffer<uint64_t[1000]> addresses;
+RWStructuredBuffer<uint> buffer;
+
+[shader("compute")]
+[numthreads(1, 1, 1)]
+void computeMain(uint3 dispatchThreadID: SV_DispatchThreadID, uint groupIndex: SV_GroupIndex)
+{
+    printf("\nfrom gpu: %llu", addresses[0]);
+}
\ No newline at end of file