Somehow the part would not be triggered without it,
ending up with system glm not being detected properly on Linux.
I'm not 100% sure I understood why it did not work, but the patch fixes the detection of glm for me. (An initial guess was that the HEADERONLY var might be seen as a string, and thus not evaluated as a bool without the ${} operator; but then it should have always been true, since strings are not a false constant).
Somehow the part would not be triggered without it, ending up with system glm not being detected properly on Linux.
I'm not 100% sure I understood why it did not work, but the patch fixes the detection of glm for me. (An initial guess was that the HEADERONLY var might be seen as a string, and thus not evaluated as a bool without the
${}operator; but then it should have always been true, since strings are not a false constant).