1 files changed, 5 insertions, 0 deletions
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 01792ae11f..a558c1ff96 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -4341,6 +4341,11 @@ void darwin::Link::ConstructJob(Compilation &C, const JobAction &JA,
 
             // darwin_crt2 spec is empty.
           }
+          // By default on OS X 10.8 and later, we don't link with a crt1.o
+          // file and the linker knows to use _main as the entry point.  But,
+          // when compiling with -pg, we need to link with the gcrt1.o file,
+          // so pass the -no_new_main option to tell the linker to use the
+          // "start" symbol as the entry point.
           if (getDarwinToolChain().isTargetMacOS() &&
               !getDarwinToolChain().isMacosxVersionLT(10, 8))
             CmdArgs.push_back("-no_new_main");