Are there tools to transform source code in C++ to the source code in C/C++, but with instantiated (unrolled) templates?

This seems already answered on SO

• Debugging template instantiations
• link 2
• link 3 (with a nice paper too)
• How do you debug heavily templated code in c++?

The Idea/principle from Alexey Frunze to use the disassembled code is quite good, together with the use of simplified templates there is a pretty good chance to understand exactly what it does.

Edit 1 There are a few other possibilities on how to get an understanding of the things which the compiler had done

1. Use: gcc -S -O1 {yourcode.cpp} to get the assembly and use the tool c++filt (its a part of binutils to convert the disassembly to C-Code if you feel more comfortable with C-Code
2. Use: g++ -fdump-tree-original file.cpp to get some (pseudo) C++ code
3. Use the MSVC++ debugger with the breakpoint after the last instantiation and see all types and values which are the parameters of the instantiated template
4. Use: GCC XML for generating XML with instantiated templates (FAQ)
5. To know how the compiler instantiated and optimized the templates you can use Clang: -emit-llvm to get the LLVM IR, and use llvm-dis to convert it to text
6. CPP insights is a website of a LLVM based tool to see instantiations

You could work around the problem by placing a deliberate error inside the instantiation or its parameters, then you'd have the compiler (assuming decent versions: gcc 4.8, clang, etc) output something along the lines of: "error with template XXX instantiated with A=int, B=float, ..".