Under MS-Windows, if two different shared libraries have the same name, their produced binaries will be the same, even if their output directories differ.
A minimal example:
cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
project(TestDuplicateNamesMSVC LANGUAGES C)
set(libname prime)
set(libdir1 ${CMAKE_BINARY_DIR}/lib1)
set(libdir2 ${CMAKE_BINARY_DIR}/lib2)
# NOTE: The output names of both libraries are the _same_,
# yet they are built in _different_ directories
# shared library 1
add_library(prime1 SHARED prime1.c)
set_target_properties(prime1 PROPERTIES
POSITION_INDEPENDENT_CODE ON
RUNTIME_OUTPUT_NAME ${libname}
RUNTIME_OUTPUT_DIRECTORY_RELEASE ${libdir1}
OUTPUT_NAME ${libname}
LIBRARY_OUTPUT_DIRECTORY ${libdir1}
)
# shared library 2
add_library(prime2 SHARED prime2.c)
set_target_properties(prime2 PROPERTIES
POSITION_INDEPENDENT_CODE ON
RUNTIME_OUTPUT_NAME ${libname}
RUNTIME_OUTPUT_DIRECTORY_RELEASE ${libdir2}
OUTPUT_NAME ${libname}
LIBRARY_OUTPUT_DIRECTORY ${libdir2}
)
- Build
cmake -B build
cmake --build build --config Release
- Compare binaries under MS-Windows
fc /b .\build\lib1\prime.dll .\build\lib2\prime.dll
yields FC: no differences encountered.
- Compare binaries under Linux
diff ./build/lib1/libprime.so ./build/lib2/libprime.so
yields Binary files build/lib1/libprime.so and build/lib2/libprime.so differ.
Tested with MSVC 19.29 under Windows 10 and GCC 10.2 under Linux, both with x64 architecture.