Introducing the "linker_weak" linkage type. This will be used for Objective-C

metadata types which should be marked as "weak", but which the linker will
remove upon final linkage. For example, the "objc_msgSend_fixup_alloc" symbol is
defined like this:

       .globl l_objc_msgSend_fixup_alloc
       .weak_definition l_objc_msgSend_fixup_alloc
       .section __DATA, __objc_msgrefs, coalesced
       .align 3
l_objc_msgSend_fixup_alloc:
        .quad   _objc_msgSend_fixup
        .quad   L_OBJC_METH_VAR_NAME_1

This is different from the "linker_private" linkage type, because it can't have
the metadata defined with ".weak_definition".


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107205 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 0 deletions

diff --git a/include/llvm/MC/MCAsmInfo.h b/include/llvm/MC/MCAsmInfo.h
index 8516de0..b76be03 100644
--- a/include/llvm/MC/MCAsmInfo.h
+++ b/include/llvm/MC/MCAsmInfo.h
@@ -85,6 +85,11 @@ namespace llvm {
     /// be passed through the assembler but be removed by the linker.  This
     /// is "l" on Darwin, currently used for some ObjC metadata.
     const char *LinkerPrivateGlobalPrefix;   // Defaults to ""
+
+    /// LinkerWeakGlobalPrefix - This prefix is used for symbols that are marked
+    /// "weak" and should be passed through the assembler, but be removed by the
+    /// linker.  This is "l" on Darwin, currently used for some ObjC metadata.
+    const char *LinkerWeakGlobalPrefix;      // Defaults to ""
     
     /// InlineAsmStart/End - If these are nonempty, they contain a directive to
     /// emit before and after an inline assembly statement.
@@ -335,6 +340,9 @@ namespace llvm {
     const char *getLinkerPrivateGlobalPrefix() const {
       return LinkerPrivateGlobalPrefix;
     }
+    const char *getLinkerWeakGlobalPrefix() const {
+      return LinkerWeakGlobalPrefix;
+    }
     const char *getInlineAsmStart() const {
       return InlineAsmStart;
     }