Xiang or Masayuki do you have any experience with that and tips?
> Wiadomość napisana przez Alan C. Assis <acas...@gmail.com> w dniu 25 lip > 2025, o godz. 17:29: > > I don't know, I don't use C++ !!! > > Maybe Xiang or Masayuki has some suggestions, because they use it with > NuttX! > > BR, > > Alan > >> On Fri, Jul 25, 2025 at 12:14 PM Bartek22 <bartol2...@gmail.com> wrote: >> >> Thanks for reply, so what is the solution in that case and how can I use >> libc++ from arm toolchain to avoid this issue? >> Best regards, >> Bartek >> >>> Wiadomość napisana przez Alan C. Assis <acas...@gmail.com> w dniu 25 >> lip 2025, o godz. 16:57: >>> >>> Hi Bart, >>> >>> You cannot replace NuttX libc with another external libc because the >> kernel >>> is tightly coupled to it. >>> >>> Some functions could work fine, but others will create issues. In the >> past >>> all kernel libc used the same name as these libc functions for >>> applications, not when a function is kernel specific it will include the >>> prefix nx_. >>> >>> Probably some kernel functions are still dependent on those same libc >> names >>> used by applications, in this case replacing them with an external libc >>> will be an issue. >>> >>> BR, >>> >>> Alan >>> >>>> On Fri, Jul 25, 2025 at 9:54 AM Bartek22 <bartol2...@gmail.com> wrote: >>>> >>>> I tried to compile simple app from NuttX with standard library from >>>> toolchain and I'm getting this errors: >> arm-none-eabi/include/stdlib.h:39:3: >>>> error: conflicting declaration 'typedef struct div_t div_t' 39 | } >> div_t; | >>>> ^~~~~ Because it sees definitions from NuttX and toolchain library, I'm >>>> using latest ARM toolchain 14.3. >>>> >>>> pt., 25 lip 2025 o 14:36 Bartek22 <bartol2...@gmail.com> napisał(a): >>>> >>>>> I’m working on integrating NuttX into an existing C++ project, but I’m >>>>> facing several issues. >>>>> >>>>> Background >>>>> Initially, I tried using symbolic links to connect my application to >>>> NuttX >>>>> apps/external and build everything with CMake. However, since NuttX >> does >>>>> not fully support CMake, I changed my approach: >>>>> >>>>> My application’s CMake script now executes NuttX’s configure, make, and >>>>> make export steps. >>>>> >>>>> After that, my application links against the NuttX libraries that were >>>>> built. >>>>> >>>>> The Problem >>>>> I need to use libc and libstdc++ from my ARM toolchain because I >> require >>>>> C++23 features. >>>>> I have already modified the relevant menuconfig settings, but I’m >>>>> encountering these issues: >>>>> >>>>> Conflicting declarations – Some symbols are coming from the toolchain >>>>> libraries, while others are being pulled in from NuttX, resulting in >>>>> multiple definition errors. >>>>> >>>>> Unsupported relocations – If I disable NuttX’s libc and libstdc++, I >> get >>>>> errors like: >>>>> "... dangerous relocation: unsupported relocation ..." >>>>> I’m unsure how to cleanly integrate NuttX with a standalone C++ >>>>> application while still using the toolchain’s standard libc and >> libstdc++ >>>>> (instead of NuttX’s minimal libc). >>>>> >>>>> What I’ve Tried >>>>> I looked at this example: >>>>> https://nuttx.apache.org/docs/latest/guides/cpp_cmake.html >>>>> >>>>> However, when I modify it to use C++23 and enable C++23 features, I >> still >>>>> encounter the same problems. >>>>> >>>>> I also want to avoid the PX4 firmware approach, where they compile >> NuttX >>>>> from their CMake file into libraries and then link to them. While this >>>>> might solve the issue, I’m looking for a simpler approach. >>>>> >>>>> Question >>>>> What is the recommended way to: >>>>> >>>>> Build NuttX while using the ARM toolchain’s standard libc and >> libstdc++? >>>>> Integrate NuttX into a standalone CMake-based C++23 project without >>>> symbol >>>>> conflicts? >>>>> >>>> >>
