Last update of libpng corrupts pcmanfm

Question

After upgrading libpng 1.2 to 1.4, pcmanfm cannot be launched.
BTW, the mirror I used is ftp.archlinux.org.
$ ldd /usr/bin/pcmanfm
linux-gate.so.1 => (0xb771f000)
libgtk-x11-2.0.so.0 => /usr/lib/libgtk-x11-2.0.so.0 (0xb7355000)
libgdk-x11-2.0.so.0 => /usr/lib/libgdk-x11-2.0.so.0 (0xb72c3000)
libgdk_pixbuf-2.0.so.0 => /usr/lib/libgdk_pixbuf-2.0.so.0 (0xb72a9000)
libcairo.so.2 => /usr/lib/libcairo.so.2 (0xb7236000)
libpango-1.0.so.0 => /usr/lib/libpango-1.0.so.0 (0xb71f4000)
libgthread-2.0.so.0 => /usr/lib/libgthread-2.0.so.0 (0xb71f0000)
libfam.so.0 => /usr/lib/libfam.so.0 (0xb71ea000)
libdbus-glib-1.so.2 => /usr/lib/libdbus-glib-1.so.2 (0xb71cd000)
libgobject-2.0.so.0 => /usr/lib/libgobject-2.0.so.0 (0xb7193000)
libglib-2.0.so.0 => /usr/lib/libglib-2.0.so.0 (0xb70e0000)
libhal-storage.so.1 => /usr/lib/libhal-storage.so.1 (0xb70d6000)
libhal.so.1 => /usr/lib/libhal.so.1 (0xb70c6000)
libdbus-1.so.3 => /usr/lib/libdbus-1.so.3 (0xb708d000)
libpthread.so.0 => /lib/libpthread.so.0 (0xb7074000)
libstartup-notification-1.so.0 => /usr/lib/libstartup-notification-1.so.0 (0xb706c000)
libc.so.6 => /lib/libc.so.6 (0xb6f24000)
libX11.so.6 => /usr/lib/libX11.so.6 (0xb6e0a000)
libm.so.6 => /lib/libm.so.6 (0xb6de4000)
libXext.so.6 => /usr/lib/libXext.so.6 (0xb6dd6000)
libXrender.so.1 => /usr/lib/libXrender.so.1 (0xb6dcd000)
libXinerama.so.1 => /usr/lib/libXinerama.so.1 (0xb6dca000)
libXi.so.6 => /usr/lib/libXi.so.6 (0xb6dbc000)
libXrandr.so.2 => /usr/lib/libXrandr.so.2 (0xb6db5000)
libXcursor.so.1 => /usr/lib/libXcursor.so.1 (0xb6dac000)
libpangocairo-1.0.so.0 => /usr/lib/libpangocairo-1.0.so.0 (0xb6da2000)
libXcomposite.so.1 => /usr/lib/libXcomposite.so.1 (0xb6d9f000)
libXdamage.so.1 => /usr/lib/libXdamage.so.1 (0xb6d9b000)
libXfixes.so.3 => /usr/lib/libXfixes.so.3 (0xb6d96000)
libatk-1.0.so.0 => /usr/lib/libatk-1.0.so.0 (0xb6d7c000)
libgio-2.0.so.0 => /usr/lib/libgio-2.0.so.0 (0xb6cec000)
libpangoft2-1.0.so.0 => /usr/lib/libpangoft2-1.0.so.0 (0xb6cc8000)
libfreetype.so.6 => /usr/lib/libfreetype.so.6 (0xb6c44000)
libfontconfig.so.1 => /usr/lib/libfontconfig.so.1 (0xb6c15000)
libgmodule-2.0.so.0 => /usr/lib/libgmodule-2.0.so.0 (0xb6c12000)
libpng12.so.0 => not found
libpng12.so.0 => not found
libpng12.so.0 => not found
libpixman-1.so.0 => /usr/lib/libpixman-1.so.0 (0xb6bb9000)
libpng12.so.0 => not found
libxcb-render-util.so.0 => /usr/lib/libxcb-render-util.so.0 (0xb6bb5000)
libxcb-render.so.0 => /usr/lib/libxcb-render.so.0 (0xb6bae000)
libxcb.so.1 => /usr/lib/libxcb.so.1 (0xb6b96000)
libz.so.1 => /usr/lib/libz.so.1 (0xb6b80000)
librt.so.1 => /lib/librt.so.1 (0xb6b77000)
libpcre.so.0 => /lib/libpcre.so.0 (0xb6b45000)
/lib/ld-linux.so.2 (0xb7720000)
libxcb-aux.so.0 => /usr/lib/libxcb-aux.so.0 (0xb6b42000)
libxcb-event.so.1 => /usr/lib/libxcb-event.so.1 (0xb6b3f000)
libxcb-atom.so.1 => /usr/lib/libxcb-atom.so.1 (0xb6b3a000)
libSM.so.6 => /usr/lib/libSM.so.6 (0xb6b32000)
libICE.so.6 => /usr/lib/libICE.so.6 (0xb6b1b000)
libdl.so.2 => /lib/libdl.so.2 (0xb6b17000)
libresolv.so.2 => /lib/libresolv.so.2 (0xb6b03000)
libexpat.so.1 => /usr/lib/libexpat.so.1 (0xb6adc000)
libXau.so.6 => /usr/lib/libXau.so.6 (0xb6ad9000)
libXdmcp.so.6 => /usr/lib/libXdmcp.so.6 (0xb6ad4000)
libuuid.so.1 => /lib/libuuid.so.1 (0xb6ad0000)

Answer 1

ngoonee wrote:
godlikejay wrote:Yep, I should update the system fully. But I think it is also an example of faulty dependency handling. Cairo can only works with libpng 1.2.*, but not libpng 1.4.*, then it should not specify the dependency of libpng to be "libpng>=1.2.37".
I do not know if pacman can check the reverse dependency(I mean, check if the packages depends on the to-be-upgrade packages supports the new version), but if it can, in my case with the correctly dependency set, at least a warning should be raised as the old cairo does not support libpng1.4 to notify what might go wrong.
Versioned deps break more than they solve, and add a LOT of work to packagers (they have to know, beforehand, exactly what versions of the library don't break the API/ABI/what-have-you?)
In the end, rolling release means versioned deps should be minimized, since part of the assumption is that everyone runs the same (updated) software and libs.
They really add a lot of work to packagers, but I don't understand why they break more than they solve. Don't they make Arch stabler and better?
As in every major release API .etc might be changed in a big chance, packages should take care of it. "A package requires >=libpng1.2  and <libpng1.3" sounds like a reasonable dep claim. And I think it doesn't avoid the minimum deps rule, or doesn't break it a lot.
Anyway, it is just my idea. I'm still a linux rookie, so that there must be something I said wrong. Hope I didn't offend you too much