C++ frontend only compiler (convert C++ to C)

c++ c embedded cross-platform
Tim Ring picture Tim Ring · Dec 2, 2009 · Viewed 10.8k times · Source

I'm currently managing some C++ code that runs on multiple platforms from a single source tree (Win32, Linux, Verifone CC terminals, MBED and even the Nintendo GBA/DS). However I need to build an app targetted at an embedded platform for which there is no C++ compiler (C only). I remmber that many of the early C++ compilers were only front-ends stitting on existing C compilers (Glockenspiel for example used MSC). Are there any such 'frontend' C++ compilers in use today that will generate C code.

                      Tools            Platform
                      -----------      ------------

                ______Visual C++ _____ WIN32
               /
              /_______MBED (ARM)_______MBED (ARM dev board).
             /
            /_________GCC (x86)________Linux
           /
Source____/___________GCC (ARM)________GBA/DS
          \
           \__________SDA______________Verifone Verix CC Terminals
            \
             \________ARM SDT__________Verifine VerixV CC terminals
              \
               \______????_____________Renases M8/16/32.
                \
                 \____????_____________Z8 family.

The last two platforms I have good C compilers for but no C++.

As you can see I'm supporting a large variety of platforms and I share a large body of library code (and some app code).

Answer

Jay Conrod picture Jay Conrod · Dec 2, 2009

If you use LLVM, llvm-g++ will compile your C++ code to LLVM bitcode, and llc has a backend which converts bitcode to C.

You could write commands like this:

llvm-g++ -emit-llvm -c foo.cpp -o foo.o
llc -march=c <foo.o >foo.c

Related questions

Compiling an application for use in highly radioactive environments

We are compiling an embedded C++ application that is deployed in a shielded device in an environment bombarded with ionizing radiation. We are using GCC and cross-compiling for ARM. When deployed, our application generates some erroneous data and crashes more …

Read More
Is there any alternative to using % (modulus) in C/C++?

I read somewhere once that the modulus operator is inefficient on small embedded devices like 8 bit micro-controllers that do not have integer division instruction. Perhaps someone can confirm this but I thought the difference is 5-10 time slower than with …

Read More
Is there any reason to use C instead of C++ for embedded development?

Question I have two compilers on my hardware C++ and C89 I'm thinking about using C++ with classes but without polymorphism (to avoid vtables). The main reasons I’d like to use C++ are: I prefer to use “inline” functions …

Read More