Index: cfe/trunk/lib/Sema/SemaChecking.cpp =================================================================== --- cfe/trunk/lib/Sema/SemaChecking.cpp +++ cfe/trunk/lib/Sema/SemaChecking.cpp @@ -8955,6 +8955,16 @@ LHS = LHS->IgnoreParenImpCasts(); RHS = RHS->IgnoreParenImpCasts(); + if (!S.getLangOpts().CPlusPlus) { + // Avoid warning about comparison of integers with different signs when + // RHS/LHS has a `typeof(E)` type whose sign is different from the sign of + // the type of `E`. + if (const auto *TET = dyn_cast(LHS->getType())) + LHS = TET->getUnderlyingExpr()->IgnoreParenImpCasts(); + if (const auto *TET = dyn_cast(RHS->getType())) + RHS = TET->getUnderlyingExpr()->IgnoreParenImpCasts(); + } + // Check to see if one of the (unmodified) operands is of different // signedness. Expr *signedOperand, *unsignedOperand; Index: cfe/trunk/test/Sema/compare.c =================================================================== --- cfe/trunk/test/Sema/compare.c +++ cfe/trunk/test/Sema/compare.c @@ -391,3 +391,16 @@ void test12(unsigned a) { if (0 && -1 > a) { } } + +// PR36008 + +enum PR36008EnumTest { + kPR36008Value = 0, +}; + +void pr36008(enum PR36008EnumTest lhs) { + __typeof__(lhs) x = lhs; + __typeof__(kPR36008Value) y = (kPR36008Value); + if (x == y) x = y; // no warning + if (y == x) y = x; // no warning +}