PlatformIO IDE v 2.2.0, Core 3.6.7 VSCode v 1.35.1 Linux Mint v 17.2 gcc v 4:4.8.2-1ubuntu6 I want to display some info about a Class using "typeid", and I know that requires having build_unflags = -fno-rtti in my platformio.ini, which I have. But I also want to not REQUIRE that a user enable rtti, because of the additional memory it uses. So I want to do something like this: #if <something that positively tells the compiler that rtti is enabled> virtual const char* getClassName() { return typeid(*this).name(); } #endif and use the same #if / #endif around the single line that actually displays the Class name in the debug message. But I’ve tried all kinds of things for that , and nothing seems to detect that rtti is enabled, because my method is never defined and my display code is never called. I tried: #if _GXX_RTTI, which I found a reference to here on this forum, but that didn't work - it never evaluated to TRUE, so my method was never defined and my debug message was never displayed. Ditto for _CPP_RTTI, which I found on another forum. Is there something that will tell the preprocessor that rtti is enabled, or not? Thanks! -- Sent from: http://gcc.1065356.n8.nabble.com/gcc-Help-f629689.html