fglrx-core 2:15.200-0ubuntu4: fglrx-core kernel module failed to build [error: implicit declaration of function ‘read_cr4’]

DKMS make.log for fglrx-core-15.200 for kernel 4.0.4-040004-generic (x86_64)
Tue May 19 00:32:40 EDT 2015
/usr/sbin/dkms: line 74: cd: /var/lib/dkms/fglrx/15.200/build: No such file or directory
AMD kernel module generator version 2.1
doing Makefile based build for kernel 2.6.x and higher
rm -rf *.c *.h *.o *.ko *.a .??* *.symvers
make -C /lib/modules/4.0.4-040004-generic/build SUBDIRS=/var/lib/dkms/fglrx-core/15.200/build/2.6.x modules
make[1]: Entering directory '/usr/src/linux-headers-4.0.4-040004-generic'
  CC [M] /var/lib/dkms/fglrx-core/15.200/build/2.6.x/firegl_public.o
/var/lib/dkms/fglrx-core/15.200/build/2.6.x/firegl_public.c: In function ‘kcl_mem_pat_setup’:
/var/lib/dkms/fglrx-core/15.200/build/2.6.x/firegl_public.c:4499:9: error: implicit declaration of function ‘read_cr4’ [-Werror=implicit-function-declaration]
         cr4 = read_cr4();
         ^
/var/lib/dkms/fglrx-core/15.200/build/2.6.x/firegl_public.c:4500:9: error: implicit declaration of function ‘write_cr4’ [-Werror=implicit-function-declaration]
         write_cr4(cr4 & ~X86_CR4_PGE);
         ^
/var/lib/dkms/fglrx-core/15.200/build/2.6.x/firegl_public.c: At top level:
/var/lib/dkms/fglrx-core/15.200/build/2.6.x/firegl_public.c:6424:12: warning: ‘KCL_fpu_save_init’ defined but not used [-Wunused-function]
 static int KCL_fpu_save_init(struct task_struct *tsk)
            ^
cc1: some warnings being treated as errors
scripts/Makefile.build:258: recipe for target '/var/lib/dkms/fglrx-core/15.200/build/2.6.x/firegl_public.o' failed
make[2]: *** [/var/lib/dkms/fglrx-core/15.200/build/2.6.x/firegl_public.o] Error 1
Makefile:1390: recipe for target '_module_/var/lib/dkms/fglrx-core/15.200/build/2.6.x' failed
make[1]: *** [_module_/var/lib/dkms/fglrx-core/15.200/build/2.6.x] Error 2
make[1]: Leaving directory '/usr/src/linux-headers-4.0.4-040004-generic'
Makefile:88: recipe for target 'kmod_build' failed
make: *** [kmod_build] Error 2
build failed with return value 2

ProblemType: Package
DistroRelease: Ubuntu 15.04
Package: fglrx-core 2:15.200-0ubuntu4
ProcVersionSignature: Ubuntu 3.19.0-16.16-generic 3.19.3
Uname: Linux 3.19.0-16-generic x86_64
ApportVersion: 2.17.2-0ubuntu1
Architecture: amd64
DKMSKernelVersion: 4.0.4-040004-generic
Date: Tue May 19 00:32:43 2015
DuplicateSignature: dkms:fglrx-core:2:15.200-0ubuntu4:/var/lib/dkms/fglrx-core/15.200/build/2.6.x/firegl_public.c:4499:9: error: implicit declaration of function ‘read_cr4’ [-Werror=implicit-function-declaration]
InstallationDate: Installed on 2015-05-01 (17 days ago)
InstallationMedia: Xubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422.1)
PackageVersion: 2:15.200-0ubuntu4
RelatedPackageVersions:
 dpkg 1.17.25ubuntu1
 apt 1.0.9.7ubuntu4
SourcePackage: fglrx-installer
SystemImageInfo:
 current build number: 0
 device name: ?
 channel: daily
 last update: Unknown
Title: fglrx-core 2:15.200-0ubuntu4: fglrx-core kernel module failed to build
UpgradeStatus: No upgrade log present (probably fresh install)