No matcher actually uses it, and there is no good reason for it,
as the best it can do for user is removing a single indirection
when using the pointer inside the matcher. Given the overhead of
other code that will be running during such time, it is completely
meaningless.
This also fixes compilation for PredicateMatcher<const char*>.
Swept:
`-Wpadded` in some places (where it caused extra size, instead of just
saying "hey, we padded struct at the end to align, just as standard says")
`-Wweak-vtables` everywhere (Clang)
`-Wexit-time-destructors` everywhere (Clang)
`-Wmissing-noreturn` everywhere (Clang)
The last three are enabled for Clang compilation going forward.
Also enabled `-Wunreachable-code` for Clang and GCC
