Enforcing stricter compilation warnings and fixing enum typing

[M2-TE]

On Linux (gcc, clang) and MacOS (clang), the flags -Wextra and -Wpedantic can be used in addition to the not-so-aptly-named -Wall to catch additional mishaps.

Clang caught one minor issue with the enums INVALID_VALUE and SPV_REFLECT_EXECUTION_MODE_SPEC_CONSTANT, which are constants set to 0xFFFFFFFF. Stricly speaking, the hexadecimal is an unsigned int, representing a value that the enum (int) cannot represent. To solve this, I simply cast the hexadecimal to an int, which creates an int with all bits set. Enums with an underlying type other than int are a specific extension in C, so this would be the more "correct" solution.

GCC 15 caught an issue regarding the cast from INVALID_VALUE to SpvStorageClass, writing to storage_class of SpvReflectTypeDescription.

SPIRV-Reflect/spirv_reflect.h

Lines 390 to 406 in 94e1c5e

	typedef struct SpvReflectTypeDescription {
	uint32_t id;
	SpvOp op;
	const char* type_name;
	// Non-NULL if type is member of a struct
	const char* struct_member_name;
	// The storage class (SpvStorageClass) if the type, and -1 if it does not have a storage class.
	int storage_class;
	SpvReflectTypeFlags type_flags;
	SpvReflectDecorationFlags decoration_flags;
	struct Traits {
	SpvReflectNumericTraits numeric;
	SpvReflectImageTraits image;
	SpvReflectArrayTraits array;
	} traits;

storage_class is already an int, so the cast is both unnecessary and strictly speaking an overflow.

Some comparisons with the enums have them simply cast to unsigned int beforehand to resolve issues with sign differences (most flags seem to be of unsigned int).

[CLAassistant]

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