Return the next available kind ID for a plugin diagnostic.
Declared in <llvm/IR/DiagnosticInfo.h>
int
getNextAvailablePluginDiagnosticKind();
Each time this function is called, it returns a different number. Therefore, a plugin that wants to "identify" its own classes with a dynamic identifier, just have to use this method to get a new ID and assign it to each of its classes. The returned ID will be greater than or equal to DK_FirstPluginKind. Thus, the plugin identifiers will not conflict with the DiagnosticKind values.
A fresh plugin diagnostic kind ID (>= DK_FirstPluginKind).