There are a number of different situations when symbols are requested
to be ordered in the --symbol-ordering-file that cannot be ordered for
some reason. To assist with identifying these symbols, and either
tidying up the order file, or the inputs, a number of warnings have
been added. As some users may find these warnings unhelpful, due to how
they use the symbol ordering file, a switch has also been added to
disable these warnings.
The cases where we now warn are:
* Entries in the order file that don't correspond to any symbol in the input
* Undefined symbols
* Absolute symbols
* Symbols imported from shared objects
* Symbols that are discarded, due to e.g. --gc-sections or /DISCARD/ linker script sections
* Multiple of the same entry in the order file
Reviewed by: rafael, ruiu
Differential Revision: https://reviews.llvm.org/D42475
llvm-svn: 325125
de300e66bb