QbsPM: Defines without values are not assigned 1

Source:

int main(int argc, char *argv[])
{
#if FOO
    return 0;
#else
    return 1;
#endif
}

Qbs project:

import qbs

CppApplication {
    cpp.defines: ["FOO"]
    files: ["main.cpp"]
}

Qmake project:

SOURCES += main.cpp
DEFINES += FOO

FOO region is not highlighted using Qbs, but is highlighted correctly with Qmake.

Find Usages on FOO finds it in <configuration>. For Qbs there is #define FOO while Qmake has #define FOO 1