In C++, enums can only represent "in range" values. If the backing
type is not specified, then the result of using bitwise negation on
an enum is not gaurenteed to be in range, resulting in UB.
This was caught by UBSAN, stack trace is as follows:
0. 0x000000000426e391 in spv::operator& (a=spv::MemoryAccessMaskNone,
b=(spv::MemoryAccessVolatileMask | spv::MemoryAccessAlignedMask | spv::MemoryAccessNontemporalMask | spv::MemoryAccessMakePointerVisibleMask | spv::MemoryAccessNonPrivatePointerMask | spv::MemoryAccessAliasScopeINTELMaskMask | spv::MemoryAccessNoAliasINTELMaskMask | unknown: 0xfffcffc0)) at SPIRV/spirv.hpp:2804
1. 0x00000000041e81e0 in (anonymous namespace)::TGlslangToSpvTraverser::accessChainLoad (this=0x7fffffffcbb8, type=...) at SPIRV/GlslangToSpv.cpp:5127
2. 0x00000000041bc059 in (anonymous namespace)::TGlslangToSpvTraverser::visitBinary (this=0x7fffffffcbb8, node=0x5f6a6c8) at SPIRV/GlslangToSpv.cpp:2192
3. 0x0000000003db8660 in glslang::TIntermBinary::traverse (this=0x5f6a6c8, it=0x7fffffffcbb8) at glslang/glslang/MachineIndependent/IntermTraverse.cpp:92
4. 0x0000000003db952e in glslang::TIntermAggregate::traverse (this=0x5f6a7d8, it=0x7fffffffcbb8) at glslang/glslang/MachineIndependent/IntermTraverse.cpp:175
5. 0x00000000042082db in (anonymous namespace)::TGlslangToSpvTraverser::makeGlobalInitializers (this=0x7fffffffcbb8, initializers=...) at SPIRV/GlslangToSpv.cpp:5618
6. 0x00000000041c511f in (anonymous namespace)::TGlslangToSpvTraverser::visitAggregate (this=0x7fffffffcbb8, visit=glslang::EvPreVisit, node=0x5f6a9b8) at SPIRV/GlslangToSpv.cpp:2907
7. 0x0000000003db8fb9 in glslang::TIntermAggregate::traverse (this=0x5f6a9b8, it=0x7fffffffcbb8) at glslang/glslang/MachineIndependent/IntermTraverse.cpp:159
8. 0x00000000041acc04 in glslang::GlslangToSpv (intermediate=..., spirv=..., logger=0x7fffffffdc38, options=0x7fffffffdc2f) at SPIRV/GlslangToSpv.cpp:10398
9. 0x0000000003bfd6f1 in CompileAndLinkShaderUnits (compUnits=...) at StandAlone/StandAlone.cpp:1547
10. 0x0000000003bfe2f8 in CompileAndLinkShaderFiles (Worklist=...) at StandAlone/StandAlone.cpp:1640
11. 0x0000000003bfec2c in singleMain () at StandAlone/StandAlone.cpp:1713
12. 0x0000000003bff4dd in main (argc=5, argv=0x7fffffffe3d8) at StandAlone/StandAlone.cpp:1767
5939e32b87