Use cmake's target_sources(), and general cmake file cleanup.

CHANGELOG.md

@@ -1,5 +1,40 @@
 ## Fips Changelog
 
+- **05-Dec-2022**: Another code cleanup, mainly focusing on the cmake script files.
+  Since the last cleanup bumped the minimal cmake version to 3.21 it was possible
+  to make use of other 'modern cmake' features which had been added in the meantime.
+  Most importantly, that's the ability to create 'empty' build targets, and then add
+  sources files afterwards. Fips now creates build targets in the ```fips_begin_*()```
+  macros instead of ```fips_end_*()```. This allows to simplify the implementation:
+  target properties and sources no longer need to be stored until ```fips_end```,
+  but instead can be added directly to the target now. Also, it's now finally possible
+  to place cmake ```target_*``` commands inside the ```fips_begin/end``` block, instead
+  of after the ```fips_end_*()``` (which worked, but just didn't look right).
+
+  The following other changes have been applied:
+
+  - The default warning level for MSVC builds has been bumped to /W3. Use
+    ```target_compile_options``` inside an ```if (FIPS_MSVC)``` block to tweak
+    warnings if necessary.
+  - A new compiler identification warning: ```FIPS_APPLE_CLANG```, this is set
+    in addiiton to ```FIPS_CLANG``` to identify Apple's Clang fork. Checking
+    specifically for Apple's Clang is mainly useful for warning hygiene.
+
+  A number of fips macros have been deprecated in favour of 'modern cmake' functions
+  or other existing fips macros:
+  These macros behave as before, but print a deprecated warning:
+    - ```fips_project``` is deprecated, use ```project``` instead
+    - ```fips_finish``` is deprecated, should be removed
+    - ```fips_begin_module``` and ```fips_end_module``` are deprecated,
+      use ```fips_begin_lib``` and ```fips_end_lib``` instead
+    - ```fips_include_dirs``` is deprecated, instead if possible use ```target_include_directories```,
+      or (less ideal) the older ```include_directories``` function
+    - ```fips_add_subdirectory``` is deprecated, use ```add_subdirectory``` instead
+    - ```fips_vs_warning_level``` and ```fips_vs_disable_warning``` is deprecated,
+      use ```target_compile_options``` instead
+
+  PR: https://github.com/floooh/fips/pull/291
+
 - **01-Dec-2022**: A general code cleanup, modernization and simplification session:
     - fips now uses the cmake-presets in cmake 3.21 and later for communicating
       build config arguments to cmake. Running './fips gen' will write
@@ -9,7 +44,7 @@
       new approach is that it better integrates with IDEs which support
       build configuration from cmake presets (such as VSCode with the CMake Tools
       extension).
-    - ...this means the minimal required cmake version is now 3.21, which in
+    - ...this means the minimal required make version is now 3.21, which in
       turn will enable a couple for simplifications in the future
     - VSCode support has been totally rewritten. This now expects the
       [CMake Tools](https://marketplace.visualstudio.com/items?itemName=ms-vscode.cmake-tools)
@@ -47,6 +82,8 @@
     - General cleanup (mainly remove unused variables and imports) with the help
       of Pylance, and cleanup white space.
 
+  PR: https://github.com/floooh/fips/pull/290
+
 - **16-May-2022**: fips will now always call ```cmake --build``` instead of
   invoking the build tools ```make```, ```ninja``` or ```xcodebuild``` directly.
   This should "just work" and not require any changes on your project.