Error in implicit conversions when enums are involved

Description
DXC seems to be having some issues when there are bit shift operations with enums. Other bit operators seem to work fine but not bit shifts. While I haven't checked the C++ spec I believe HLSL mirrors C++'s behavior. Despite that this error is not something I've seen or was able to reproduce in any of the C++ compilers that I've tested. This leads me to believe that there might be an issue with DXC.

Steps to Reproduce
Pretty simple repro case:

enum E : uint {
    A,
    B
};

float4 PSMain() : SV_Target0 {
    uint e = E::A << 1u;    
    return 0.0;
}

And the error is:

error: cannot convert from 'unsigned int' to 'E'

Replacing << with | for example works fine.

Godbolt link: https://godbolt.org/z/nKThYcs1z

Actual Behavior
Pretty sure that this type of operations shouldn't throw an error.

Environment

• DXC version: Trunk (6b4b0eb5)
• Host Operating System: Linux

Start by compiling the provided HLSL repro with DXC trunk and compare the enum shift with the working bitwise-OR form. Trace the implicit-conversion handling for enum expressions; done means the shift expression compiles without the reported conversion error while preserving the expected behavior.