dtrace @370.40.1 build failure: 'sys/elf.h' file not found

[cave-canem]

port installed dtrace
The following ports are currently installed:
  dtrace @168_0 (active)

sudo port -vd upgrade dtrace
...
In file included from /opt/MacPorts/var/macports/build/_opt_macports-ports_sysutils_dtrace/dtrace/work/dtrace-370.40.1/lib/libelf/clscook.c:40:
In file included from /opt/MacPorts/var/macports/build/_opt_macports-ports_sysutils_dtrace/dtrace/work/dtrace-370.40.1/lib/libelf/decl.h:59:
/opt/MacPorts/var/macports/build/_opt_macports-ports_sysutils_dtrace/dtrace/work/dtrace-370.40.1/lib/libelf/machelf.h:33:10: fatal error: 'sys/elf.h' file not found
#include <sys/elf.h>
         ^
1 error generated.
...
/opt/MacPorts/var/macports/build/_opt_macports-ports_sysutils_dtrace/dtrace/work/dtrace-370.40.1/lib/libelf/machelf.h:33:10: fatal error: 'sys/elf.h' file not found
#include <sys/elf.h>
         ^
1 error generated.

** BUILD FAILED **


The following build commands failed:
	CompileC build/dtrace.build/Release/libelf.build/Objects-normal/x86_64/clscook.o lib/libelf/clscook.c normal x86_64 c com.apple.compilers.llvm.clang.1_0.compiler
	CompileC build/dtrace.build/Release/libelf.build/Objects-normal/x86_64/clscook_ELF64.o lib/libelf/clscook_ELF64.c normal x86_64 c com.apple.compilers.llvm.clang.1_0.compiler
(2 failures)
Command failed: cd "/opt/MacPorts/var/macports/build/_opt_macports-ports_sysutils_dtrace/dtrace/work/dtrace-370.40.1" && /usr/bin/xcodebuild  -target "ctfconvert" -configuration Deployment build INSTALL_PATH="/opt/MacPorts/bin"  OBJROOT="/opt/MacPorts/var/macports/build/_opt_macports-ports_sysutils_dtrace/dtrace/work/dtrace-370.40.1/build/" SYMROOT="/opt/MacPorts/var/macports/build/_opt_macports-ports_sysutils_dtrace/dtrace/work/dtrace-370.40.1/build/" MACOSX_DEPLOYMENT_TARGET=10.9 ARCHS=x86_64 SDKROOT="" CLANG_CXX_LIBRARY="libc++"
Exit code: 65
Error: Failed to build dtrace: command execution failed
DEBUG: Error code: NONE
DEBUG: Backtrace: command execution failed
    while executing
"$procedure $targetname"
Error: See /opt/MacPorts/var/macports/logs/_opt_macports-ports_sysutils_dtrace/dtrace/main.log for details.
DEBUG: invalid command name "::ui_init"
    while executing
"::ui_init $priority $prefix $channels($priority) {*}$args"
    ("uplevel" body line 2)
    invoked from within
"uplevel 1 $body"

See the detailed log in the attachment.

[cave-canem]

main.log