[llvm] r314000 - llvm-ar: Don't add an unnecessary alignment in gnu mode.

[Rafael Espindola via llvm-commits]

Author: rafael
Date: Fri Sep 22 11:16:13 2017
New Revision: 314000

URL: http://llvm.org/viewvc/llvm-project?rev=314000&view=rev
Log:
llvm-ar: Don't add an unnecessary alignment in gnu mode.

This is mostly for getting stricter testing in preparation for future
changes.

Modified:
    llvm/trunk/lib/Object/ArchiveWriter.cpp
    llvm/trunk/test/Object/archive-symtab.test

Modified: llvm/trunk/lib/Object/ArchiveWriter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Object/ArchiveWriter.cpp?rev=314000&r1=313999&r2=314000&view=diff
==============================================================================
--- llvm/trunk/lib/Object/ArchiveWriter.cpp (original)
+++ llvm/trunk/lib/Object/ArchiveWriter.cpp Fri Sep 22 11:16:13 2017
@@ -351,7 +351,8 @@ writeSymbolTable(raw_fd_ostream &Out, ob
 
   // ld64 requires the next member header to start at an offset that is
   // 4 bytes aligned.
-  unsigned Pad = OffsetToAlignment(Out.tell(), 4);
+  unsigned Alignment = isBSDLike(Kind) ? 4 : 2;
+  unsigned Pad = OffsetToAlignment(Out.tell(), Alignment);
   while (Pad--)
     Out.write(uint8_t(0));
 

Modified: llvm/trunk/test/Object/archive-symtab.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/archive-symtab.test?rev=314000&r1=313999&r2=314000&view=diff
==============================================================================
--- llvm/trunk/test/Object/archive-symtab.test (original)
+++ llvm/trunk/test/Object/archive-symtab.test Fri Sep 22 11:16:13 2017
@@ -122,3 +122,11 @@ RUN: llvm-ar --format=bsd rcsU %t.a %p/I
 RUN: FileCheck --check-prefix=MACHO-SYMTAB-ALIGN %s < %t.a
 MACHO-SYMTAB-ALIGN: !<arch>
 MACHO-SYMTAB-ALIGN-NEXT: #1/12           {{..........}}  0     0     0       36        `
+
+With a gnu symbol table we only align to two
+8 + 60 + 14 = 82
+RUN: rm -f %t.a
+RUN: llvm-ar --format=gnu rcsD %t.a %p/Inputs/trivial-object-test.macho-x86-64
+RUN: FileCheck --check-prefix=GNU-SYMTAB-ALIGN %s < %t.a
+GNU-SYMTAB-ALIGN: !<arch>
+GNU-SYMTAB-ALIGN-NEXT: /               0           0     0     0       14        `