problem with libpng while installing matplotlib on mountain lion

[ashkan.ekhtiari@…]

sudo port install py27-matplotlib
dyld: DYLD_ environment variables being ignored because main executable (/usr/bin/sudo) is setuid or setgid
Password:
--->  Computing dependencies for py27-matplotlib
--->  Dependencies to be installed: libpng py27-configobj py27-dateutil py27-tz py27-pyobjc-cocoa py27-pyobjc py27-py2app py27-macholib py27-modulegraph py27-altgraph py27-tkinter tk tcl xorg-libX11 xorg-kbproto xorg-libXau xorg-xproto xorg-libXdmcp xorg-libxcb xorg-libpthread-stubs xorg-xcb-proto libxml2
--->  Configuring libpng
Error: org.macports.configure for port libpng returned: configure failure: command execution failed
Error: Failed to install libpng
Please see the log file for port libpng for details:
    /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_ports_graphics_libpng/libpng/main.log
Error: The following dependencies were not installed: libpng py27-configobj py27-dateutil py27-tz py27-pyobjc-cocoa py27-pyobjc py27-py2app py27-macholib py27-modulegraph py27-altgraph py27-tkinter tk tcl xorg-libX11 xorg-kbproto xorg-libXau xorg-xproto xorg-libXdmcp xorg-libxcb xorg-libpthread-stubs xorg-xcb-proto libxml2
To report a bug, follow the instructions in the guide:
    http://guide.macports.org/#project.tickets
Error: Processing of port py27-matplotlib failed

==========================================================================

cat /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_ports_graphics_libpng/libpng/main.log
version:1
:debug:main changing euid/egid - current euid: 0 - current egid: 0
:debug:main egid changed to: 501
:debug:main euid changed to: 502
:debug:main Executing org.macports.main (libpng)
:debug:main Privilege de-escalation not attempted as not running as root.
:debug:main Skipping completed org.macports.archivefetch (libpng)
:debug:main Privilege de-escalation not attempted as not running as root.
:debug:main Skipping completed org.macports.fetch (libpng)
:debug:main Privilege de-escalation not attempted as not running as root.
:debug:main Skipping completed org.macports.checksum (libpng)
:debug:main Privilege de-escalation not attempted as not running as root.
:debug:main Skipping completed org.macports.extract (libpng)
:debug:main Privilege de-escalation not attempted as not running as root.
:debug:main Skipping completed org.macports.patch (libpng)
:debug:main Privilege de-escalation not attempted as not running as root.
:debug:configure configure phase started at Fri Mar  1 22:38:03 CET 2013
:notice:configure --->  Configuring libpng
:debug:configure Using compiler 'Mac OS X clang'
:debug:configure Executing org.macports.configure (libpng)
:debug:configure Environment: CPATH='/opt/local/include' CFLAGS='-pipe -O2 -arch x86_64' CPPFLAGS='-I/opt/local/include' CXXFLAGS='-pipe -O2 -arch x86_64' LIBRARY_PATH='/opt/local/lib' MACOSX_DEPLOYMENT_TARGET='10.8' CXX='/usr/bin/clang++' CC_PRINT_OPTIONS_FILE='/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_graphics_libpng/libpng/work/.CC_PRINT_OPTIONS' F90FLAGS='-pipe -O2 -m64' LDFLAGS='-L/opt/local/lib -arch x86_64' OBJC='/usr/bin/clang' FCFLAGS='-pipe -O2 -m64' INSTALL='/usr/bin/install -c' OBJCFLAGS='-pipe -O2 -arch x86_64' FFLAGS='-pipe -O2 -m64' CC_PRINT_OPTIONS='YES' CC='/usr/bin/clang'
:debug:configure Assembled command: 'cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_graphics_libpng/libpng/work/libpng-1.5.14" && ./configure --prefix=/opt/local'
:debug:configure Executing command line:  cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_graphics_libpng/libpng/work/libpng-1.5.14" && ./configure --prefix=/opt/local 
:info:configure sh: line 0: cd: /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_graphics_libpng/libpng/work/libpng-1.5.14: No such file or directory
:info:configure Command failed:  cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_graphics_libpng/libpng/work/libpng-1.5.14" && ./configure --prefix=/opt/local 
:info:configure Exit code: 1
:error:configure org.macports.configure for port libpng returned: configure failure: command execution failed
:debug:configure Error code: NONE
:debug:configure Backtrace: configure failure: command execution failed
    while executing
"$procedure $targetname"
:info:configure Warning: targets not executed for libpng: org.macports.activate org.macports.configure org.macports.build org.macports.destroot org.macports.install
:error:configure Failed to install libpng
:debug:configure couldn't open "/System/Library/Frameworks/Tcl.framework/Versions/8.5/Resources/tclIndex": no such file or directory
    while executing
"open [file join $dir tclIndex]"
:notice:configure Please see the log file for port libpng for details:
    /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_ports_graphics_libpng/libpng/main.log

[mf2k (Frank Schima)]

In the future, please use WikiFormatting, fill in the Port field with the failed port and Cc that port's maintainer(s). Also, please attach the main.log instead of pasting it in the description unformatted.

What happens when you clean libpng and try again?