I'm trying to compile gnupg-2.1.0 for Debian Wheezy, I've downloaded and compiled the required libraries (libgpg-error-1.17, libgcrypt-1.6.2, libksba-1.3.2, libassuan-2.1.3, and pth-2.0.7 in that order) via ./configure, make, make install. I then added /usr/local/lib to /etc/ld.so.conf and then ran ldconfig so that gnupg could find the libraries.

Gpupg compiles fine but upon attempting to run either ./agent/gpg-agent or ./g10/g I am greated with this error:

alpha@virtual:~/gnupg-2.1.0$ ./agent/gpg-agent --version
./agent/gpg-agent: /lib/i386-linux-gnu/libgpg-error.so.0: no version information available (required by ./agent/gpg-agent)
./agent/gpg-agent: /lib/i386-linux-gnu/libgpg-error.so.0: no version information available (required by /usr/local/lib/libgcrypt.so.20)
./agent/gpg-agent: relocation error: ./agent/gpg-agent: symbol gpgrt_set_alloc_func, version GPG_ERROR_1.0 not defined in file libgpg-error.so.0 with link time reference

ldd ./agent/gpg-agent produces

root@virtual:/home/alpha/gnupg-2.1.0# ldd ./agent/gpg-agent
./agent/gpg-agent: /lib/i386-linux-gnu/libgpg-error.so.0: no version information available (required by ./agent/gpg-agent)
./agent/gpg-agent: /lib/i386-linux-gnu/libgpg-error.so.0: no version information available (required by /usr/local/lib/libgcrypt.so.20)
        linux-gate.so.1 =>  (0xb7750000)
        libgcrypt.so.20 => /usr/local/lib/libgcrypt.so.20 (0xb7698000)
        libgpg-error.so.0 => /lib/i386-linux-gnu/libgpg-error.so.0 (0xb7694000)
        libassuan.so.0 => /usr/lib/i386-linux-gnu/libassuan.so.0 (0xb7681000)
        libnpth.so.0 => /usr/local/lib/libnpth.so.0 (0xb767d000)
        libpthread.so.0 => /lib/i386-linux-gnu/i686/cmov/libpthread.so.0 (0xb7664000)
        libc.so.6 => /lib/i386-linux-gnu/i686/cmov/libc.so.6 (0xb74ff000)
        librt.so.1 => /lib/i386-linux-gnu/i686/cmov/librt.so.1 (0xb74f6000)
        /lib/ld-linux.so.2 (0xb7751000)

Why is this error occuring and how could I fix it?

Resolution

Resolved by adding /usr/local/lib to LD_LIBRARY_PATH via export LD_LIBRARY_PATH=/usr/local/lib:${LD_LIBRARY_PATH} and echo /usr/local/lib > /etc/ld.so.conf.d/local.conf

Solution 1:

Root cause of problem

The error is occurring because at compile time, it is properly searching the /usr/local/lib path before it is searching the system default path, thus at link time, all symbols resolve. However at runtime, your /usr/local/lib path is not searched before the pre-existing /lib/i386-linux-gnu so it is finding the identically named library in the latter directory before your desired library in /usr/local/lib.

Solution, easy version: Global library search path (with caveat)

The easy version is to insert /usr/local/lib in your LD_LIBRARY_PATH environment variable or /etc/ld.so.conf config then run ldconfig. For the "fast" solution, you want /usr/local/lib before anything else.

However, this is the unfortunate bit, you do not want to force all of your programs to search /usr/local/lib before the system library path (eg: /lib/i386-linux-gnu) -- this makes it highly likely you will cause a version conflict with a system library used by another program provided by your system or package manager and cause the system program to fail. This means to "do things right", you do not want to use LD_LIBRARY_PATH, LD_PRELOAD or /etc/ld.so.conf to force your search path. (In fact, LD_PRELOAD should be avoided outside of development work)

Solution, stable version: Update ELF RPATH

Instead, when compiling your own versions of applications, you can use the LD_RUN_PATH environment variable (gnu ld & gold) or setting LDFLAGS to -Wl,-rpath /usr/local/lib to manage the internal library-search-path of your binaries (including .so shared library dependencies)

So for example, you could run the following to configure your library:

export LD_RUN_PATH=/usr/local/lib
./configure --prefix=/usr/local <--yourflags>
make install

My experience with this technique has been on HP-UX where the chatr utility will show you the embedded rpath (and the link flag is +b instead of -rpath). readelf or objdump will probably show the rpath on linux.

patchelf claims to be able to update the rpath in existing binaries on linux x86, but I haven't tested it myself.

Solution 2:

I had the same problems with Ubuntu (12 and 14 and 16, Gnome and Xfce, completely different machines ....) and I compiled the whole stuff from scratch. Interesting, does not help at all. same errors: Version 2 required, no communication with pinentry and so on.

Removed the old 1.4 - stupid mistake! They are designed to co-exist (1.x and 2.x).

The solution actually was this: Do install gnupg2 with the Ubuntu CLI:

sudo apt-get install gnupg2 

did the job. With all 4 machines and all Versions. So simple, so cool. Works like a charm :-) SOLVED (at least on my zoo of installations)