gcc: problem with -ld or -lz not found

Rhyader · 08-26-2020, 12:30 PM

And yet another question...
This one is about gcc and C programming. Please bear in mind that I am NOT a programer! I am a moron who can type "make all" - and sometimes figure out where to stick a code patch - but that's about the size of it. I'm trying to compile my MUD on this new installation. It compiles OK on other systems, so it is not my code, it is the gcc setup on this computer. The first time it produced an error saying it could not find zlib.h. I put the zlib.h file in a directory (hope it was the right one) and now I get a different error:

Code:

/usr/lib64/gcc/x86_64-suse-linux/7/../../../../x86_64-suse-linux/bin/ld: cannot find -lz
collect2: error: ld returned 1 exit status
make[1]: *** [Makefile:58: smaug] Error 1
make: *** [Makefile:42: all] Error 2

What does all this "/../../../../" gobbeldygook refer to?

Help ?

boughtonp · 08-26-2020, 03:31 PM

Quote:

Originally Posted by Rhyader

What does all this "/../../../../" gobbeldygook refer to?

"../" means parent directory so "/usr/lib64/gcc/x86_64-suse-linux/7/../../../../x86_64-suse-linux/bin/ld" is shortened to "/usr/x86_64-suse-linux/bin/ld"

It seems that the ld executable is being executed, so other than being confusing and not ideal, that bit isn't relevant to the error.

This is the significant part:

Code:

ld: cannot find -lz
collect2: error: ld returned 1 exit status

As per "ld --help", the -l option expects a library name to follow it, and similarly -z should be followed by something, so you need to find whatever is trying to call ld and correct the arguments it is providing.

Edit: Corrected based on messages below, the -l option expects a library name, and this error indicates a failure to find the library named "z" (aka zlib), and specifically the development version zlib-devel (which is usually in a separate package to the main library).

knudfl · 08-29-2020, 03:58 PM

Quote:

ld: cannot find -lz

Please install zlib-devel

Code:

# zypper in zlib-devel

Rhyader · 08-29-2020, 08:23 PM

That Works !
Thanks !
I thought I had the zlib stuff installed already,
but apparently I did not have all of it.
Now the program compiles without even any warnings.

chown -fR us your/base*

hazel · 08-30-2020, 05:37 AM

In most distros, libraries come in two packages, not one. The runtime library will be called something like libfoo, and this is needed if you want to run or build any programs using this library. The other is the so-called development package which contains the library headers and programmer documentation and is only needed for building software, not for running it. In Debian-type distros, this will be called libfoo-dev, and in Red Hat distros, libfoo-devel.

When you run the build's configure script, it checks for the headers, not the libraries as such. That's why it often reports that it can't find a library which you know you have. You need to install the development package.

The notation../../../ is not "gobbledegook". It simply indicates that to find the target from the link, you need to go back up the file tree. ".." means parent directory. So:
/usr/lib64/gcc/x86_64-suse-linux/7/.. is /usr/lib64/gcc/x86_64-suse-linux
/usr/lib64/gcc/x86_64-suse-linux/7/../.. is /usr/lib64/gcc and
/usr/lib64/gcc/ x86_64-suse-linux/7/../../.. is usr/lib64