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I am trying to compile a program, and the linking fails with the following message:

gcc -O2 -pipe -Wl,--export-dynamic tkAppInit.o -L/home/dimitriv/ns-allinone-2.35/tk8.5.10/unix -ltk8.5 \
-L/home/dimitriv/ns-allinone-2.35/tcl8.5.10/unix -ltcl8.5 -lX11 -ldl -lieee -lm -Wl,-rpath,/home/dimitriv/ns-allinone-2.35/lib -o wish /usr/bin/ld: cannot find -lX11
collect2: error: ld returned 1 exit status

however, my $LD_LIBRARY_PATH contains the directory where X11 has been installed:

echo $LD_LIBRARY_PATH
/share/apps/cim/lib:/opt/ns2/otcl-1.13:/opt/ns2/lib:/home/dimitriv/local/lib:

and the libraries seem to be correctly installed.

ls /home/dimitriv/local/lib | grep X11
libX11.a
libX11.la
libX11.so
libX11.so.6
libX11.so.6.3.0
libX11-xcb.a
libX11-xcb.la
libX11-xcb.so
libX11-xcb.so.1
libX11-xcb.so.1.0.0
X11

Why can't make locate the libraries and do the linking?

Yann Droneaud
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user000001
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3 Answers3

5

The LD_LIBRARY_PATH contains paths to shared libraries which are used by the loader (ld program) to get the program to execute.

During compilation, include directories are used. During linking, object libraries are needed. The last one is the kind you are missing.

You might have to install a package to get the X11 development libraries. On Linux, the package is called libX11-devel. To install,

sudo yum install libX11-devel             # for Redhat, Fedora, etc.

or

sudo apt-get install libX11-devel         # for Ubuntu, etc.
wallyk
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  • The *devel* packages are needed to provide the `libX11.so` which `ld` is looking for. (note: the `libX11.so` is usually a symbolic link to `libX11.so.6`, which is in turn a symbolic link to the current version of the library `libX11.so.6.3.0`). See `ldconfig` – Yann Droneaud Dec 21 '12 at 08:37
  • Unfortunately I can't install anything with yum, because I am not a sudoer. I have installed `libX11-1.5.0` from source. I can only find libX11-dev in a package, could you point out where I could locate the source for it? Also @ydroneaud, as you can see `libX11.so` exists in the above directory... Maybe `libX11-dev` is not needed after all? – user000001 Dec 21 '12 at 08:54
  • sudo apt-get install libx11-dev is the correct syntax – M.Hefny Aug 01 '22 at 04:36
1

as you can see in the compilation command itself:

gcc -O2 -pipe -Wl,--export-dynamic tkAppInit.o -L/home/dimitriv/ns-allinone-2.35/tk8.5.10/unix -ltk8.5 \ 
-L/home/dimitriv/ns-allinone-2.35/tcl8.5.10/unix -ltcl8.5 -lX11 -ldl -lieee -lm -Wl,-rpath,/home/dimitriv/ns-allinone-2.35/lib -o wish

the path 

-L/home/dimitriv/local/lib

is not added.Add it in your make file and then check.

Vijay
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  • ok I will check. But shouldn't it check in the LD_LIBRARY_PATH anyway? – user000001 Dec 21 '12 at 08:33
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    @user828193 only at runtime. The `LD_LIBRARY_PATH` variable is only used by the dynamic linker when running the program. – Yann Droneaud Dec 21 '12 at 08:39
  • I couldn't figure out where to change the Makefile, but I added the flag, ran it from the command line and seemed to work. I will report back to see it has any side effects. – user000001 Dec 21 '12 at 08:47
1

Solution: Install the missing packages using

sudo apt-get install gconf-service libasound2 libatk1.0-0 libc6 libcairo2 libcups2 libdbus-1-3 libexpat1 libfontconfig1 libgcc1 libgconf-2-4 libgdk-pixbuf2.0-0 libglib2.0-0 libgtk-3-0 libnspr4 libpango-1.0-0 libpangocairo-1.0-0 libstdc++6 libx11-6 libx11-xcb1 libxcb1 libxcomposite1 libxcursor1 libxdamage1 libxext6 libxfixes3 libxi6 libxrandr2 libxrender1 libxss1 libxtst6 ca-certificates fonts-liberation libappindicator1 libnss3 lsb-release xdg-utils wget
Alan
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    This answer is the best in cases where you have `sudo` permission and can install packages. The reason I wanted to compile the package though was precisely the missing permission. – user000001 Dec 16 '18 at 08:14