CMake configuration with BUILD_SHARED_LIBS=OFF creates a malformed pkg-config file

[traversaro]

In particular, the libpcap.pc contains the following malformed line:

Libs: -L${libdir} -l

To reproduce the issue:

git clone https://github.com/the-tcpdump-group/libpcap
cd libpcap
mkdir build
cd build
cmake -DBUILD_SHARED_LIBS:BOOL=OFF ..
cat libpcap.pc

[traversaro]

The problem seems to be due to https://github.com/the-tcpdump-group/libpcap/blob/libpcap-1.9.1/CMakeLists.txt#L2309 .

[guyharris]

Not Linux-specific - I reproduced it on macOS.

[guyharris]

Removing the unset() gives

CMake Error at CMakeLists.txt:2608 (install):
  install TARGETS given target "pcap" which does not exist in this directory.

so more work is needed.

[guyharris]

Doesn't seem to happen on 1.10.

[guyharris]

Duplicate of #1009