Switch from gcc to clang
Clang requires static variables to have ctors explicitly called
Ignore additional clang warnings
Ignore tautologocial comparison warning
Add additional flags for clang to debug.starsha and release.starsha
Don't try to capture a VLA (Even by reference)
Fix "error: braces around scalar initializer"
Ignore unused private field in Sabot test, since it is actually used / what we're testing around