Previously we used separate placeholders for builtin linker flags:
* CMAKE_<LANG>_LINK_FLAGS for EXECUTABLEs
* CMAKE_SHARED_LIBRARY_CREATE_<LANG>_FLAGS for SHARED libraries
* CMAKE_SHARED_MODULE_CREATE_<LANG>_FLAGS for MODULE libraries
These are now always replaced by the empty string, so drop them
from our rule variables.
This variable define how the link step is done. Possible values are:
* DRIVER: the compiler is used as driver for the link step
* LINKER: the linker is used directly for the link step.
The commit 98fea8205e (Compiler/TI: Avoid response file usage for
linker, 2020-07-11, v3.19.0-rc1~495^2) disabled linker file usage by
default. The previous settings were working, even if not for all cases.
Restore them and add an explanation in a comment.
Issue: #22233
These changes are in preparation of compiler generated dependencies support
for Makefiles generators
* compiler output and dependency target can be different for Makefiles generators
* resolve inconsistency naming for dependency file place-holder
In commit a548a52230 (Compiler/TI: Refactor C/CXX to use a common file,
2020-07-11) a variable named `prefix` has been introduced.
It is set in the callers namespace because it was defined inside a
macro, not a function.
Avoid such generic variable name.
The object and library files have to be listed after the `--run-linker`
flag.
But after this flag the `--cmd_file` flag for response files cannot be
used any more.
Putting the whole command line into a response file would work, but
this is not supported by CMake (yet).
By adding the compiler flags via `<FLAGS>` to the linker call,
the linker can decide which default library to use.
CMake replaces `<FLAGS>` by the content of `CMAKE_<LANG>_FLAGS`.
So any relevant flag needs to be defined in this variable, preferably
in a toolchain file.
The compiler flags have to be specified before the `--run_linker`
flag and the linker flags afterwards.
Replaces Merge-request !4890
