[lld] r318284 - [COFF] Always include the size of the string table size field

[Martin Storsjo via llvm-commits]

Author: mstorsjo
Date: Wed Nov 15 00:18:25 2017
New Revision: 318284

URL: http://llvm.org/viewvc/llvm-project?rev=318284&view=rev
Log:
[COFF] Always include the size of the string table size field

Even if we don't actually write any string table contents, the
4 byte size for the string table will always be written. Make
sure we accommodate for this in the file size. Since this size
is aligned up, this would seldom be an issue in practice.

Differential Revision: https://reviews.llvm.org/D39891

Added:
    lld/trunk/test/COFF/strtab-size.s
Modified:
    lld/trunk/COFF/Writer.cpp

Modified: lld/trunk/COFF/Writer.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/COFF/Writer.cpp?rev=318284&r1=318283&r2=318284&view=diff
==============================================================================
--- lld/trunk/COFF/Writer.cpp (original)
+++ lld/trunk/COFF/Writer.cpp Wed Nov 15 00:18:25 2017
@@ -564,8 +564,7 @@ void Writer::createSymbolAndStringTable(
     PointerToSymbolTable = FileOff;
     FileOff += OutputSymtab.size() * sizeof(coff_symbol16);
   }
-  if (!Strtab.empty())
-    FileOff += Strtab.size() + 4;
+  FileOff += Strtab.size() + 4;
   FileSize = alignTo(FileOff, SectorSize);
 }
 

Added: lld/trunk/test/COFF/strtab-size.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/COFF/strtab-size.s?rev=318284&view=auto
==============================================================================
--- lld/trunk/test/COFF/strtab-size.s (added)
+++ lld/trunk/test/COFF/strtab-size.s Wed Nov 15 00:18:25 2017
@@ -0,0 +1,216 @@
+# REQEUIRES: x86
+
+# Test that the strtab size is included in the allocation even if the
+# strtab itself is empty. To achieve this, we need a number of symbols N
+# where alignTo(N*18, 512) < alignTo(N*18 + 4, 512), where the first
+# positive N fulfilling that is 199.
+
+# RUN: llvm-mc -triple=x86_64-windows-msvc %s -filetype=obj -o %t.obj
+# RUN: lld-link -out:%t.exe -entry:main %t.obj -debug
+
+# If the size of the strtab isn't allocated for, llvm-readobj would
+# output SymbolCount: 0 (and dumpbin.exe would error out with "invalid file
+# or disk full, cannot seek to 0x1602").
+
+# RUN: llvm-readobj -file-headers %t.exe | FileCheck %s
+# CHECK: SymbolCount: 199
+
+.global main
+.text
+main:
+sym0:
+sym1:
+sym2:
+sym3:
+sym4:
+sym5:
+sym6:
+sym7:
+sym8:
+sym9:
+sym10:
+sym11:
+sym12:
+sym13:
+sym14:
+sym15:
+sym16:
+sym17:
+sym18:
+sym19:
+sym20:
+sym21:
+sym22:
+sym23:
+sym24:
+sym25:
+sym26:
+sym27:
+sym28:
+sym29:
+sym30:
+sym31:
+sym32:
+sym33:
+sym34:
+sym35:
+sym36:
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+sym38:
+sym39:
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+sym41:
+sym42:
+sym43:
+sym44:
+sym45:
+sym46:
+sym47:
+sym48:
+sym49:
+sym50:
+sym51:
+sym52:
+sym53:
+sym54:
+sym55:
+sym56:
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+sym58:
+sym59:
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+sym114:
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+sym162:
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+sym185:
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+sym190:
+sym191:
+sym192:
+sym193:
+sym194:
+  ret