This change primarily fixes some -Wconversion warnings from gcc, but
also silences a warning triggered in glslang_tab.cpp, which is generated
code from bison.
There are still several GCC conversion warnings in Types.h due to the
use of bit fields that will be resolved in a future change.
According to the extension SPV_GOOGLE_decorate_string,
OpDecorateString (or OpMemberDecorateString) ought to be capable of
supporting multiple literal strings. Each literal strings are padded
with null terminator to make word alignment. The layout is:
Inst | Target | Decoration | Literal String, Literal String, ...
The codebase seems to use both “#pragma once“ approach, and “#ifndef / #define” approach,
so I picked pragma once as that one is less typing & less brittle.
When glslang is built with some other build system and lumped/unity builds are used,
without the include guards some headers would get included multiple times, leading to duplicate
declaration errors.
This fixes various issues related to gcc's strict-aliasing warning
by using unions. It also handles various cases hit with
gcc's missing-declarations warning.
- member initializing order in some constructors
- missing default branches in switch-case
- uninitialized variable if switch-case default (uncritical because
program would exit)
- && and || brace warnings in if()
