This is probably a dumb question, but I'm trying to get a small CMake project to compile and no luck. The error message I get is as follows:

CMake Error at cmake/Modules/FindLibM.cmake:80 (message):
  Could not find LibM headers or libraries!
Call Stack (most recent call first):
  CMakeLists.txt:53 (find_package)

Looking at the source code, i see this in FindLibM.cmake:

# Check for the header files:
find_path( LibM_INCLUDE_DIR
  NAMES math.h
  HINTS /usr/include /usr/local/include /usr/local/bic/include
  PATH_SUFFIXES
  )
#set( LibM_INCLUDE_DIR TRUE )



# Check for the libraries:
set( LibM_LIBRARIES "" )

find_library( LibM_LIBRARY
  NAMES m
  HINTS /usr/lib /usr/local/lib /usr/lib/x86_64-linux-gnu /usr/lib/i386-linux-gnu
  #PATH_SUFFIXES 
  NO_DEFAULT_PATH
  )

It goes without saying but I'm no expert on C/C++, so I'm just trying to follow other derivations in nixpkgs. I believe math.h is part of the standard library, which I believe (?) is glibc. The derivation for this includes a libm.so (I'm no teven sure if it's the right library), but including it as part of the buildInputs doesn't do anything. It also has no header files.

So, where can I find that header? I believe this program will compile with either the header files or the library. Lastly, do you think patching the cmake code to help it find this "LibM" library could work?

EDIT

I managed to get it working by running substituteInPlace in the CMake file, now it finds all the libraries but for some annoying reason the C compiler complaints that it can't find the headers, despite them being there. I'll see what I can do.