I am currently debugging some stuff and I noticed that on macOS the clang version provided by Xcode has quite a lot of flags set by default.
For example, following flags are set by default:
...
-Wno-reorder-init-list \
-Wno-implicit-int-float-conversion \
-Wno-c99-designator \
-Wno-final-dtor-non-final-class \
-Wno-extra-semi-stmt \
-Wno-misleading-indentation \
-Wno-quoted-include-in-framework-header \
-Wno-implicit-fallthrough \
-Wno-enum-enum-conversion \
-Wno-enum-float-conversion \
-Wno-elaborated-enum-base \
-Wno-reserved-identifier \
-Wno-gnu-folding-constant \
...
When using different clang compilers many of these flags are missing. Now I was wondering which component sets all these flags. Between the execution of the clang wrapper found in /usr/bin/clang and the actual compilers there are not too many steps but I am not entirely sure, which component sets all these flags.