what means is defined in DSO /lib64/libz.so.1

[Nils Philippsen]

On Tue, 2012-03-06 at 17:10 +0000, Sérgio Basto wrote:
> Hi , I found this error 
> 
> /usr/bin/ld: /usr/lib/gcc/x86_64-redhat-linux/4.7.0/../../../../lib64/libgpac_static.a(base_encoding.o): undefined reference to symbol 'deflate'                                                              
> /usr/bin/ld: note: 'deflate' is defined in DSO /lib64/libz.so.1 so try
> adding it to the linker command
> line                                                                                                   
> /lib64/libz.so.1: could not read symbols: Invalid
> operation                                            
> collect2: error: ld returned 1 exit status
> 
> 
> Could someone help me , to understand what happens ? 

AIUI, it looks like the code you try to compile uses the deflate()
function from libz, and doesn't link it directly (i.e. the "-lz"
compiler option) but indirectly (i.e. links a library which uses libz).
You need to explicitly link all libraries that you use, you may not
depend on other libraries pulling these in.

Nils
-- 
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