On 2021-02-23, Bob <obs...@protonmail.com> wrote: > Hi, > > I am trying to make a custom build of libpng in my home directory, > using a libz build that I made in my home directory also. > > Both are latest version, libpng 1.6.37 same as OpenBSD's port > https://cvsweb.openbsd.org/ports/graphics/png/Makefile?rev=1.125&content-type=text/x-cvsweb-markup > and libz the latest one they published. For zlib it's 1.2.11 > from http://zlib.net/ from 2017, OpenBSD does not have a port but > base bundles a 2009 version. Since 2009, significantly an export > "inflateReset2" has been added.
As you have seen it is difficult to have library functions in one version in base and in another version built elsewhere (whether that's in $HOME or in ports). Ports only does this for libraries where there's really no other choice and where that has been done they're used *very* rarely (the port can then not depend on any libraries which pull in the library from base). Currently that is libbind (used only by asdig and zeek) and openssl (used as a static library by sslscan, and dynamic for nrpe and nsca-ng). > I'll start with the detail problem, and discuss the reproduction at the > bottom: > > > This has brought me to the bizarre issue that the libpng build plainly > refuses to link to my custom libz file /home/myuser/lib/libz.so.1 . > Instead, it insists with linking to the OS' global > /usr/lib/libz.so.5.0 . This is as expected really, it looks for the higher library version number. > I have reduced the issue to the libpng build step where it produces > libpng.so: > > /usr/local/bin/egcc -shared -fPIC -DPIC -o .libs/libpng.so.16.37 > .libs/png.o .libs/pngerror.o .libs/pngget.o .libs/pngmem.o > .libs/pngpread.o .libs/pngread.o .libs/pngrio.o .libs/pngrtran.o > .libs/pngrutil.o .libs/pngset.o .libs/pngtrans.o .libs/pngwio.o > .libs/pngwrite.o .libs/pngwtran.o .libs/pngwutil.o -L/home/myuser/lib > -lm -lz -Og -g -fstack-protector-all > [with or without: -Wl,--version-script=libpng.vers] > [with or without: -Wl,-t] You might get somewhere further with something like "-nostdlib -L/home/myuser/lib -L/usr/lib". You might need either rpath or change to using static libs. (not relevant to libpng which is in C, but if you try to build C++ software with GCC rather than Clang you will often run into problems with incompatible standard libraries too). > What appears is that GCC ignores the "-L" search path given to it. -L adds, it doesn't overwrite. Hopefully you're just doing this to use pngfix; if you try and replace the installed libpng with one built like this you're likely to end up with all sorts of problems.
