Don't drop alignment info on local common symbols.

- On COFF the .lcomm directive has an alignment argument.
- On ELF we fall back to .local + .comm

Based on a patch by NAKAMURA Takumi.

Fixes PR9337, PR9483 and PR10128.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138976 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCNullStreamer.cpp b/lib/MC/MCNullStreamer.cpp
index 9577af0..a6c0adb 100644
--- a/lib/MC/MCNullStreamer.cpp
+++ b/lib/MC/MCNullStreamer.cpp
@@ -59,8 +59,8 @@
     virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {}
     virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
                                   unsigned ByteAlignment) {}
-    virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size) {}
-
+    virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
+                                       unsigned ByteAlignment) {}
     virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
                               unsigned Size = 0, unsigned ByteAlignment = 0) {}
     virtual void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,