Function flagsWithoutAliasCache

src/ast/ast_typedecl.cpp:486–496

Save/clear/restore the lazy findAlias cache bits (PR #2849) so they don't enter the lookup/semantic hash. The bits reflect runtime cache state, not type identity; two compiles of the same source can leave them differently set depending on findAlias lifecycle, and we don't want that to leak.

    // type identity; two compiles of the same source can leave them differently
    // set depending on findAlias lifecycle, and we don't want that to leak.
    static __forceinline uint32_t flagsWithoutAliasCache(const TypeDecl * td) {
        TypeDecl * mut = const_cast<TypeDecl*>(td);
        const bool savedV = mut->aliasCacheValid;
        const bool savedH = mut->aliasCacheHasAlias;
        mut->aliasCacheValid = false;
        mut->aliasCacheHasAlias = false;
        const uint32_t result = mut->flags;
        mut->aliasCacheValid = savedV;
        mut->aliasCacheHasAlias = savedH;
        return result;
    }

    void TypeDecl::getLookupHash(uint64_t & hash) const {
        hash = hashmix(hash, baseType);