typeof is supported by everything[1] except the C standard. It was rejected in the 1990s and nobody on the committee seems to want to revisit the decision. To

typeof is supported by everything[1] except the C standard. It was rejected in the 1990s and nobody on the committee seems to want to revisit the decision. To be fair, typeof is not as useful without statement expressions (`({ ... })`), and statement expressions aren't as widely supported. [1] All the major compilers support it (clang, GCC, IBM, Intel, Microsoft, Solaris, etc), plus or minus underscores in the identifier.