When I was incorporating a software library written in C into an existing demo project(used a C++ mbed library) I encountered this problem. The demo project would compile just fine, but after I replaced the existing main file by my own, this error occurred.
At this point I hadn't yet thought about the fact that the mbed library that I needed was written in C++. My own main file was a .c file that #include
the mbed header file. As a result I used my normal C source as if it was a C++ source. Therefore the compiler that was used to compile my main file was the C compiler.
This C compiler then encountered a #include
of a module that actually does not exist (within its scope), as it's not a C++ compiler.
Only after I inspected the output of the build log I realised the various source C and C++ files were compiled by more that 1 compiler(the c++ compiler). The project used used compilers arm-none-eabi-c++ and arm-none-eabi-gcc (for embedded systems) as seen below.
Compile log:
Building file: ../anyfile.cpp
Invoking: MCU C++ Compiler
arm-none-eabi-c++ <A lot of arguments> "../anyfile.cpp"
Finished building: ../anyfile.cpp
Building file: ../main.c
Invoking: MCU C Compiler
arm-none-eabi-gcc <A lot of arguments> "../main.c"
In file included from <Project directory>\mbed/mbed.h:21:0,
from ../main.c:16:
<Project directory>\mbed/platform.h:25:19: fatal error: cstddef: No such file or directory
compilation terminated.
Of course in a C++ environment cstddef exists, but in a C environment cstddef doesn't exist, in stead it's just C's implementation of stddef.
In other words, cstddef does not exist in the C compiler.
I resolved this problem by renaming my main.c file to main.cpp and the rest of the code compiled smoothly too.
TLDR/Conclusion: When building a C++ project, avoid mixing C files with C++ files(sources and headers). If possible rename .c files to .cpp files to use the C++ compiler in stead of the C compiler where required.
g++ file.cc
where file.cc is the name of yoru file (should end in.cc
or.cpp
). If you still get the same error then your compiler installation is broken; fire up the Cygwin installer and refresh your installation of g++. Check thatgcc
andglibc
are up to date also. – M.M