[demangler] Ignore leading underscores if present

On MacOS, symbols start with a leading underscore, so just parse and
ignore it if present.

git-svn-id: https://llvm.org/svn/llvm-project/libcxxabi/trunk@351481 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 6 insertions, 2 deletions

diff --git a/src/demangle/ItaniumDemangle.h b/src/demangle/ItaniumDemangle.h
index 53107c9..9a54ff5 100644
--- a/src/demangle/ItaniumDemangle.h
+++ b/src/demangle/ItaniumDemangle.h
@@ -5143,7 +5143,7 @@ AbstractManglingParser<Derived, Alloc>::parseTemplateArgs(bool TagTemplates) {
 // extension      ::= ___Z <encoding> _block_invoke_<decimal-digit>+
 template <typename Derived, typename Alloc>
 Node *AbstractManglingParser<Derived, Alloc>::parse() {
-  if (consumeIf("_Z")) {
+  if (consumeIf("_Z") || consumeIf("__Z")) {
     Node *Encoding = getDerived().parseEncoding();
     if (Encoding == nullptr)
       return nullptr;
@@ -5156,7 +5156,7 @@ Node *AbstractManglingParser<Derived, Alloc>::parse() {
     return Encoding;
   }
 
-  if (consumeIf("___Z")) {
+  if (consumeIf("___Z") || consumeIf("____Z")) {
     Node *Encoding = getDerived().parseEncoding();
     if (Encoding == nullptr || !consumeIf("_block_invoke"))
       return nullptr;
diff --git a/test/test_demangle.pass.cpp b/test/test_demangle.pass.cpp
index 7c1fd2d..09ba043 100644
--- a/test/test_demangle.pass.cpp
+++ b/test/test_demangle.pass.cpp
@@ -29755,6 +29755,10 @@ const char* cases[][2] =
     {"_Z1fIJR1SS0_EEiDpOT_", "int f<S&, S>(S&, S&&)"},
 
     {"___Z3foo_block_invoke.25", "invocation function for block in foo"},
+
+    // Darwin adds leading underscores to symbols, just demangle them anyways.
+    {"____Z3foo_block_invoke.25", "invocation function for block in foo"},
+    {"__Z1fv", "f()"},
 };
 
 const unsigned N = sizeof(cases) / sizeof(cases[0]);