[mach-o] propagate dylib version numbers
Mach-o does not use a simple SO_NEEDED to track dependent dylibs. Instead,
the linker copies four things from each dylib to each client: the runtime path
(aka "install name"), the build time, current version (dylib build number), and
compatibility version The build time is no longer used (it cause every rebuild
of a dylib to be different). The compatibility version is usually just 1.0
and never changes, or the dylib becomes incompatible.
This patch copies that information into the NormalizedMachO format and
propagates it to clients.
llvm-svn: 222300
diff --git a/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryReader.cpp b/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryReader.cpp
index 042cca7..a05fa75 100644
--- a/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryReader.cpp
+++ b/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryReader.cpp
@@ -455,8 +455,10 @@
DependentDylib entry;
entry.path = lc + read32(&dl->dylib.name, isBig);
entry.kind = LoadCommandType(cmd);
+ entry.compatVersion = read32(&dl->dylib.compatibility_version, isBig);
+ entry.currentVersion = read32(&dl->dylib.current_version, isBig);
f->dependentDylibs.push_back(entry);
- }
+ }
break;
case LC_DYLD_INFO:
case LC_DYLD_INFO_ONLY: