Index: lib/DebugInfo/DWARF/DWARFDebugLine.cpp
===================================================================
--- lib/DebugInfo/DWARF/DWARFDebugLine.cpp
+++ lib/DebugInfo/DWARF/DWARFDebugLine.cpp
@@ -520,6 +520,11 @@
     // rudimentary sequences for address ranges [0x0, 0xsomething).
   }
 
+  // There could be hundreds or thousands of Rows in the line table. The vector
+  // will likely have an internal reserved memory block that is much bigger
+  // than necessary. Reduce the reserved capacity to conserve memory.
+  Rows.shrink_to_fit();
+
   return end_offset;
 }