clang-format crashes when formatting "requires" argument after #if-#else

[owenca]

@HazardyKnusperkeks, I got some requires-related crashes when formatting .cpp files under clang/test/. Below is one (which I reduced to the bare minimum) of them:

$ cat .clang-format
BasedOnStyle: LLVM
$ clang-format --version
clang-format version 15.0.0 (https://github.com/llvm/llvm-project 77e60bc42c48e16d646488d43210b1630cd4db49)
$ clang-format
#if 0
#else
foo();
#endif
bar(requires);
Assertion failed: (RequiresToken->getType() == TT_Unknown), function parseRequiresExpression, file UnwrappedLineParser.cpp, line 3022.
...

[llvmbot]

@llvm/issue-subscribers-bug

[llvmbot]

@llvm/issue-subscribers-clang-format

[HazardyKnusperkeks]

Review: https://reviews.llvm.org/D120512

[HazardyKnusperkeks]

As seen in the patch it just happens in the presence of preprocessor branches, but what are you doing with bar(requires)? Or how did it look before you made it minimal?

[owenca]

As seen in the patch it just happens in the presence of preprocessor branches, but what are you doing with bar(requires)? Or how did it look before you made it minimal?

Here is the original code.