The changes are part of CMP0128.
When the standard level is unset:
* Flags are added if extension mode doesn't match the compiler's default.
Previously logic only worked if LANG_EXTENSIONS was ON. Fixes#22224.
* The full flag is used. Previously CMAKE_LANG_EXTENSION_COMPILE_OPTION was
used. This was only supported for IAR.
Otherwise:
* Avoid adding flags if not necessary per the detected compiler defaults.
* Fixed check for when the requested standard is older. It now matches the
nearby comments.
I reworded the fallback comment as its logic was a bit difficult to wrap my
head around.
Run the `Utilities/Scripts/clang-format.bash` script to update
all our C++ code to a new style defined by `.clang-format`.
Use `clang-format` version 3.8.
* If you reached this commit for a line in `git blame`, re-run the blame
operation starting at the parent of this commit to see older history
for the content.
* See the parent commit for instructions to rebase a change across this
style transition commit.
Add properties and variables corresponding to CXX equivalents.
Add features for c_function_prototypes (C90), c_restrict (C99),
c_variadic_macros (C99) and c_static_assert (C11). This feature
set can be extended later.
Add a <PREFIX>_RESTRICT symbol define to WriteCompilerDetectionHeader
to conditionally represent the c_restrict feature.
