Alright, I thought that conftest.h was part of the upstream NVidia driver package, and as I was comparing with a working Ubuntu driver (331.38) to figure out what was missing, I thought that this had changed between 331.38 and 340.32.
I see now that this is Debian-only, and was probably never activated, as you mentioned. It explains why Nils Goroll had troubles with driver versions 331.38 and 319.76 as well. I attached the debdiff you requested. -- Beren Minor
diff -Nru nvidia-graphics-drivers-340.32/debian/changelog nvidia-graphics-drivers-340.32/debian/changelog --- nvidia-graphics-drivers-340.32/debian/changelog 2014-08-17 12:20:45.000000000 +0200 +++ nvidia-graphics-drivers-340.32/debian/changelog 2014-09-01 08:37:11.000000000 +0200 @@ -1,3 +1,10 @@ +nvidia-graphics-drivers (340.32-2) UNRELEASED; urgency=medium + + * Non-maintainer upload. + * Fix DRM support activation in conftest.h (Closes #731265) + + -- Beren Minor <[email protected]> Mon, 01 Sep 2014 08:35:48 +0200 + nvidia-graphics-drivers (340.32-1) unstable; urgency=medium * New upstream long lived branch release 340.32 (2014-08-12). diff -Nru nvidia-graphics-drivers-340.32/debian/module/conftest.h nvidia-graphics-drivers-340.32/debian/module/conftest.h --- nvidia-graphics-drivers-340.32/debian/module/conftest.h 2014-08-17 12:20:45.000000000 +0200 +++ nvidia-graphics-drivers-340.32/debian/module/conftest.h 2014-09-01 08:24:55.000000000 +0200 @@ -374,7 +374,7 @@ #endif /* Implement conftest.sh function drm_available */ -#if 0 +#if IS_ENABLED(CONFIG_DRM) || IS_ENABLED(CONFIG_DRM_MODULE) #define NV_DRM_AVAILABLE #else #undef NV_DRM_AVAILABLE

