Use .str() when converting StringRef to std::string in ModuleInterfaceLoader

[artemcm]

This implicit conversion is no longer correct and just happens to work when linking against the version of LLVM currently used in CI. The implicit conversion operator for std::string has been removed upstream so this change is meant to unblock being able to build against more-recent LLVM versions.

[artemcm]

@swift-ci please test

[compnerd]

This change is valid (and should be done), but a bit more context would be great. How did you find this? There was/is an implicit conversion operator for std::string that will be removed once the rebranching for trunk is done (its been removed upstream).

[artemcm]

This change is valid (and should be done), but a bit more context would be great. How did you find this? There was/is an implicit conversion operator for std::string that will be removed once the rebranching for trunk is done (its been removed upstream).

An issue was found when building Swift trunk against a newer version of LLVM, where, as you say, this behaviour is no longer supported. So this change is meant to unblock that. I will update the PR description with additional context.

[swift-ci]

Build failed
Swift Test OS X Platform
Git Sha - fd96bbd

[artemcm]

@swift-ci please test OS X platform

[swift-ci]

Build failed
Swift Test OS X Platform
Git Sha - fd96bbd

[artemcm]

Looks to be an environment filesystem access failure.
@swift-ci please test OS X platform

[swift-ci]

Build failed
Swift Test OS X Platform
Git Sha - fd96bbd

[artemcm]

@swift-ci please test OS X platform

[artemcm]

@swift-ci please test OS X platform