There is a bug in the diagnostic output of ParseHLSLRootSignature when outputting a punctuator. Instead of outputting the string literal of the token ',' it instead will treat it as an integer and output the ascii value.

Proposed solution:

Update the following switch statement to have a separate macro for PUNCUATOR that will output a string literal of the character as opposed to just the character.

For instance: https://godbolt.org/z/vbY717qMh