Fix #202. This commit switches the default type in CMake from `SHARED` to `MODULE`. Two issues have been found. ## First issue I ran into an issue while testing this commit on macOS. Here is the error I got from clang: ```shell clang: error: invalid argument '-compatibility_version 1.0.0' only allowed with '-dynamiclib' ``` After some investigation, I found out that the [`SOVERSION` and `VERSION`](https://cmake.org/cmake/help/latest/prop_tgt/SOVERSION.html) properties should not be used when building a shared library. This doesn't seem to lead to an error on Linux, but on macOS, it happens to set the following two flags: * `-compatibility_version` (given by `SOVERSION`) * `-current_version` (given by `VERSION`) However, CMake uses the `-bundle` flag when linking, instead of the `-dynamiclib` flag. I found a fix by reading the documentation: > For shared libraries, the MACHO_COMPATIBILITY_VERSION and MACHO_CURRENT_VERSION > properties can be used to override the compatibility version and current > version respectively. Setting these two flags to `OFF` removes `-compatibility_version` and `-current_version`. Perhaps we should simply remove `SOVERSION` and `VERSION`, as they're only meant to be used for shared libraries? ## Second issue OpenSSL has an API to load dynamic objects and libraries called `DSO`. When loading a provider, a call to `dlfcn_name_converter` is made to compute the name of the file: https://github.com/openssl/openssl/blob/79fa5873a9c2f2df392bc4b39146d8db37640118/crypto/dso/dso_dlfcn.c#L253-L280 Reader may notice that OpenSSL appends the macro `DSO_EXTENSION` to the end of the provider's name. `DSO_EXTENSION` is platform-specific: its value is `.so` on Unix, and `.dylib` on macOS. Because we're building a `MODULE` library here instead of a `SHARED` library, the output file's extension is `.so` instead of `.dylib`. Thus, OpenSSL fails to find the `oqs-provider` to load. To solve this issue, I used the [`SUFFIX`](https://cmake.org/cmake/help/latest/prop_tgt/SUFFIX.html) property of CMake targets to explicitely specify the extension when building for a XNU-based platform (macOS, iOS, watchOS, etc.). also change suffix on Windows. adapt CI to MODULE-defined paths.

Commits

Commits on Jul 6, 2023

Build a module instead of a shared library.