private symbols in the __DATA segment internal.
This prevents the linker from removing the symbol names. Keeping the
symbols visible enables tools to collect various information about the
symbols, for example, tools that discover whether or not a symbol gets
dirtied.
rdar://problem/48887111
Differential Revision: https://reviews.llvm.org/D61454
llvm-svn: 360359
metadata and protocol list
The leading 'l' tells ld64 to remove the symbol name, which can make
debugging difficult.
rdar://problem/47256637
Differential Revision: https://reviews.llvm.org/D59234
llvm-svn: 356156
expression
Clang emits invalid protocol metadata when a @protocol expression is used with a
forward-declared protocol. The protocol metadata is missing protocol conformance
list of the protocol since we don't have access to the definition of it in the
compiled translation unit. The linker then might end up picking the invalid
metadata when linking which will lead to incorrect runtime protocol conformance
checks.
This commit makes sure that Clang fails to compile code that uses a @protocol
expression with a forward-declared protocol. This ensures that Clang does not
emit invalid protocol metadata. I added an extra assert in CodeGen to ensure
that this kind of issue won't happen in other places.
rdar://32787811
Differential Revision: https://reviews.llvm.org/D49462
llvm-svn: 340102
When Protocol references are constructed, we need to add the reference
symbol to a COMDAT group on non-MachO object file formats (MachO handles
this by having a coalesced attribute). This adds the missing case.
llvm-svn: 306622
This allows for the coalescing of the protocol declarations. When the protocols
are declared in headers, multiple definitions of the protocol would be emitted.
Marking them as common data indicates that any one can be selected.
llvm-svn: 285073
Fangrui Song