What is Linux utility to mangle a C++ symbol name?

WilliamKF picture WilliamKF · Jul 4, 2012 · Viewed 13k times · Source

I have c++filt command to demangle a symbol, what is the tool to do the opposite and mangle a symbol name?

This would be useful if I were to want to call dlsym() on a mangled C++ function name. I'd rather not hard code the name mangling in the code since it could change over time due to new complier versions or new compiler brands being used or at present due to compiling for multiple platforms.

Is there a programatic way to get the string that represents a C++ function at runtime so that the code is compiler independent? One way to possibly do this would be to call a utility at compile time that performs the name mangling for the compiler being used and inserts the appropriate mangled C++ symbol name into a string for dlsym() to use.

Here is the closest to a solution I've found on this site which is accomplished by using a fixed C style name to indirect to C++ symbols that are defined in the library you wish to dlsym(), but if you do not have control over what that library provides, this is not an option.

Answer

Dani picture Dani · Aug 23, 2015

That's how g++ mangles names. You might implement those mangling rules on your program.

Another (crazy) solution would be to list all of the symbols in the library you want to use (it's not so difficult if you understand the format), demangle them all, and search your function's name in that list. The advantage with this method is that demangling is easier, as there is a function call to do it: abi::__cxa_demangle, from cxxabi.h header.