Don't allocate space for SHT_NOBITS sections.

llvm-svn: 246480

2 files changed, 39 insertions, 1 deletions

diff --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp
index 31f64083a87..94b42656a1c 100644
--- a/lld/ELF/Writer.cpp
+++ b/lld/ELF/Writer.cpp
@@ -63,6 +63,7 @@ public:
   uintX_t getFlags() { return Header.sh_flags; }
   uintX_t getFileOff() { return Header.sh_offset; }
   uintX_t getAlign() { return Header.sh_addralign; }
+  uint32_t getType() { return Header.sh_type; }
 
   virtual void finalize() {}
   virtual void writeTo(uint8_t *Buf) = 0;
@@ -449,7 +450,8 @@ template <class ELFT> void Writer<ELFT>::assignAddresses() {
       VA += RoundUpToAlignment(Size, Align);
     }
     Sec->setFileOffset(FileOff);
-    FileOff += RoundUpToAlignment(Size, Align);
+    if (Sec->getType() != SHT_NOBITS)
+      FileOff += RoundUpToAlignment(Size, Align);
   }
 
   // Regular sections.
diff --git a/lld/test/elf2/bss.s b/lld/test/elf2/bss.s
new file mode 100644
index 00000000000..8c766176329
--- /dev/null
+++ b/lld/test/elf2/bss.s
@@ -0,0 +1,36 @@
+// RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
+// RUN: lld -flavor gnu2 %t -o %t2
+// RUN: llvm-readobj -sections %t2 | FileCheck %s
+// REQUIRES: x86
+
+// Test that bss takes no space on disk.
+
+// CHECK:        Name: .bss
+// CHECK-NEXT:   Type: SHT_NOBITS
+// CHECK-NEXT:   Flags [
+// CHECK-NEXT:     SHF_ALLOC
+// CHECK-NEXT:     SHF_WRITE
+// CHECK-NEXT:   ]
+// CHECK-NEXT:   Address: 0x1000
+// CHECK-NEXT:   Offset: 0x1000
+// CHECK-NEXT:   Size: 4
+// CHECK-NEXT:   Link: 0
+// CHECK-NEXT:   Info: 0
+// CHECK-NEXT:   AddressAlignment: 4
+// CHECK-NEXT:   EntrySize: 0
+// CHECK-NEXT: }
+// CHECK-NEXT: Section {
+// CHECK-NEXT:   Index:
+// CHECK-NEXT:   Name:
+// CHECK-NEXT:   Type:
+// CHECK-NEXT:   Flags [
+// CHECK-NEXT:   ]
+// CHECK-NEXT:   Address:
+// CHECK-NEXT:   Offset: 0x1000
+
+
+        .global _start
+_start:
+
+        .bss
+        .zero 4