Symbols not found during linking

I have a problem with a shared library (Linux) and a program that links against this library but does not find the symbols – although they are there. That’s what I have:

A shared library “libetest.so” that is located in /usr/lib. When I do an

 readelf -Ws /usr/lib/libetest.so.0

JavaScript
​x
 
 readelf -Ws /usr/lib/libetest.so.0​

it gives (beside some others) this output:

54: 000052c0   905 FUNC    LOCAL  DEFAULT   11 ETEST_open_connection

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54: 000052c0   905 FUNC    LOCAL  DEFAULT   11 ETEST_open_connection​

Now I have an application that makes use of ETEST_open_connection(). When I build it with

gcc lib_test.cpp -DENV_LINUX -letest

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gcc lib_test.cpp -DENV_LINUX -letest​

it fails with a linker error

lib_test.cpp:(.text+0x32): undefined reference to `ETEST_open_connection'

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lib_test.cpp:(.text+0x32): undefined reference to `ETEST_open_connection'​

As shown before the symbol is there! Any idea why this fails?

Answer

Please try:

gcc -DENV_LINUX -letest lib_test.cpp

JavaScript
 
gcc -DENV_LINUX -letest lib_test.cpp​

This should be the correct argument order.

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Answer