[gstreamer-bugs] [Bug 362708] New: MinGW requires a -no-undefined flag as a linker parameter

[GStreamer (bugzilla.gnome.org)]

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  GStreamer | gstreamer (core) | Ver: 0.10.10

           Summary: MinGW requires a -no-undefined flag as a linker
                    parameter
           Product: GStreamer
           Version: 0.10.10
          Platform: Other
        OS/Version: Windows
            Status: UNCONFIRMED
          Severity: normal
          Priority: Normal
         Component: gstreamer (core)
        AssignedTo: gstreamer-bugs at lists.sourceforge.net
        ReportedBy: mrc.gran at gmail.com
         QAContact: gstreamer-bugs at lists.sourceforge.net
     GNOME version: Unspecified
   GNOME milestone: Unspecified


I have been obtaining the following error when compiling gstreamer-0.10.10
using MingW and creating shared libraries (dlls):

libtool: link: warning: undefined symbols not allowed in i686-pc-mingw32 shared
libraries

This message shows when some library dependency is missing (e.g. -lpython24,
-lws2_32 etc) and therefore not all symbols are being found when creating the
DLL. In this case, the MinGW build defaults to a static library without
reporting the error properly and stopping the build. Therefore, the user cannot
promptly spot the problem when it occurs. 

This is a rather confusing error. In order to make MinGW report a more concise
and helpful error (containing the symbols not found) and stop the build, it is
necessary to include the flag -no-undefined as a link parameter. 

Adding this flag in the LDFLAGS variable (os in some equivalent linker
variable) line of *ALL Makefiles* in *ALL gstreamer projects* (core, plugins,
gst-python etc) that configure created for MinGW corrects the problem:

LDFLAGS = -no-undefined


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