How to set the type of a variable or function to an std::string?

Question

I'm using IDA Pro and have identified a function that takes an std::string as an argument.

However when I click on the function and "Set Item Type", entering its definition:

std::__ndk1::basic_string<char,std::__ndk1::char_traits<char>,std::__ndk1::allocator<char>> funcname(const std::__ndk1::basic_string<char,std::__ndk1::char_traits<char>,std::__ndk1::allocator<char>>& foo)

I get a syntax error:

Syntax error near: std::__ndk1::basic_string

However there are other variables with this very type that IDA is able to use. Why is it failing when I try to set it?

Answer 1

IDA’s C parser does not handle some C++ syntax like namespaces. There are two options:

1. Rename the local type or struct to have no “wrong” symbols, you can use it in type declaration then
2. Use “Convert to struct*” context menu command on the argument/variable. This bypasses the C parser and sets the type directly.