OpenMP headers

[haji-ali]

I have a simple code as follows

#include <iostream>
#include <omp.h>

int main() {}

with the json file (generated by cmake)

[
{
  "directory": "./build",
  "command": "c++  -fopenmp   -std=gnu++14 -o CMakeFiles/project.dir/main.cpp.o -c ./main.cpp",
  "file": "./main.cpp"
}
]

with GCC

% c++ --version
c++ (GCC) 8.2.1 20180905 (Red Hat 8.2.1-3)

However, irony cannot fine the header file even though the c++ command is successful without errors.

 main.cpp            8  10 error           'omp.h' file not found (irony)

Any idea how I can fix this?