[SYCL]Remove unwanted check for value dependency of const vars

[srividya-sundaram]

Removed CheckValueDependent from the parameter list of function bool checkAllowedSYCLInitializer(VarDecl *VD, bool CheckValueDependent = false);

Setting this value to false by default causes compiler crash during initialization of constexprs that are value dependent, because in L4143 ValueDependent will be false irrespective of Init->isValueDependent()'s value.

ValueDependent is then switched to true here which is incorrect.

The assert in Init->isConstantInitializer(Context, false) is triggered since we never truly checked if the var is valuedependent or not.

[smanna12]

Can you add a test to show the problem?

[AaronBallman]

+1 to needing test coverage. One thing that I'm uncertain of is: the callers that don't expect a check for value dependence are now always getting a check they didn't expect. I think that's actually an improvement, but I am wondering if we're regressing any behavior here.

[premanandrao]

but I am wondering if we're regressing any behavior here.

I don't believe we are, @AaronBallman. There was an implicit assumption (prior to my changes in PR #2019) that this call would not be made in contexts where there was a value dependency, and my changes carried forward that assumption. This seems wrong now in hindisight, and @srividya-sundaram's fix seems okay to me in that context.

But I am not sure if I too am missing something deeper.

[AaronBallman]

LGTM

[smanna12]

Changes look good to me.

[premanandrao]

I am good with the changes, modulo @dm-vodopyanov's comments. If the failure still reproduces after the suggested change that would be nice.

[dm-vodopyanov]

@srividya-sundaram from internal discussion:
"After discussing with code owners, we feel its better to do as part of a separate PR and close the current PR."

LGTM, merging the PR.