[CMake] Cannot determine link language for target

[Marc-André Laverdière]

Hello CMakers,

I'm really a n00b...

So, I am building each subdirectory into a static library and I want to 
put all those libraries into a nice big dynamic library. The big dynamic 
library is the objective here.

I'm doing it as such:
ADD_LIBRARY(XYZ SHARED
${CMAKE_CURRENT_SOURCE_DIR}/stdio/libstdio.a
${CMAKE_CURRENT_SOURCE_DIR}/stdlib/libstdlib.a
${CMAKE_CURRENT_SOURCE_DIR}/string/libstring.a
${CMAKE_CURRENT_SOURCE_DIR}/time/libtime.a
${CMAKE_CURRENT_SOURCE_DIR}/wchar/libwchar.a)

Yet, I obtain the following, when I run rebuild_cache:
CMake Error: Cannot determine link language for target XYZ

What am I doing wrong? How should I proceed to build that dynamic library?

Thanks in advance for the patience and the support!


-- 
Marc-André LAVERDIÈRE, B. Eng., M. A. Sc. (in progress)
Research Assitant - Computer Security Laboratory
CIISE, Université Concordia University, Montréal, Québec, Canada
www.ciise.concordia.ca

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