dsymutil: support dwarf version mismatches between object and clang module

This adds a missing call to maybeUpdateMaxDwarfVersion when visitng a
clang module. Failing to do so will cause a failure when emitting
DWARF 4 forms into a CU that AsmPrinter believes to be DWARF 2.

rdar://problem/33666528

llvm-svn: 310392

1 files changed, 3 insertions, 1 deletions

diff --git a/llvm/tools/dsymutil/DwarfLinker.cpp b/llvm/tools/dsymutil/DwarfLinker.cpp
index fcbc2680180..f9328e42fd0 100644
--- a/llvm/tools/dsymutil/DwarfLinker.cpp
+++ b/llvm/tools/dsymutil/DwarfLinker.cpp
@@ -3325,8 +3325,10 @@ void DwarfLinker::loadClangModule(StringRef Filename, StringRef ModulePath,
   auto DwarfContext = DWARFContext::create(*ErrOrObj);
   RelocationManager RelocMgr(*this);
   for (const auto &CU : DwarfContext->compile_units()) {
-    auto CUDie = CU->getUnitDIE(false);
+    maybeUpdateMaxDwarfVersion(CU->getVersion());
+
     // Recursively get all modules imported by this one.
+    auto CUDie = CU->getUnitDIE(false);
     if (!registerModuleReference(CUDie, *CU, ModuleMap, Indent)) {
       if (Unit) {
         errs() << Filename << ": Clang modules are expected to have exactly"