[lld] r310736 - Avoid crash with local abs symbol.

[Rafael Espindola via llvm-commits]

Author: rafael
Date: Fri Aug 11 10:47:12 2017
New Revision: 310736

URL: http://llvm.org/viewvc/llvm-project?rev=310736&view=rev
Log:
Avoid crash with local abs symbol.

Modified:
    lld/trunk/ELF/Symbols.cpp
    lld/trunk/test/ELF/map-file.s

Modified: lld/trunk/ELF/Symbols.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Symbols.cpp?rev=310736&r1=310735&r2=310736&view=diff
==============================================================================
--- lld/trunk/ELF/Symbols.cpp (original)
+++ lld/trunk/ELF/Symbols.cpp Fri Aug 11 10:47:12 2017
@@ -131,8 +131,13 @@ SymbolBody::SymbolBody(Kind K, StringRef
       Name(Name) {}
 
 InputFile *SymbolBody::getFile() const {
-  if (isLocal())
-    return cast<InputSectionBase>(cast<DefinedRegular>(this)->Section)->File;
+  if (isLocal()) {
+    const SectionBase *Sec = cast<DefinedRegular>(this)->Section;
+    // Local absolute symbols actually have a file, but that is not currently
+    // used. We could support that by having a mostly redundant InputFile in
+    // SymbolBody, or having a special absolute section if needed.
+    return Sec ? cast<InputSectionBase>(Sec)->File : nullptr;
+  }
   return symbol()->File;
 }
 

Modified: lld/trunk/test/ELF/map-file.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/map-file.s?rev=310736&r1=310735&r2=310736&view=diff
==============================================================================
--- lld/trunk/test/ELF/map-file.s (original)
+++ lld/trunk/test/ELF/map-file.s Fri Aug 11 10:47:12 2017
@@ -25,6 +25,9 @@ bar:
 .long zed - .
 local:
 .comm   common,4,16
+.global abs
+abs = 0xAB5
+labs = 0x1AB5
 
 // CHECK:      Address          Size             Align Out     In      Symbol
 // CHECK-NEXT: 0000000000200158 0000000000000030     8 .eh_frame
@@ -48,12 +51,12 @@ local:
 // CHECK-NEXT: 0000000000202000 0000000000000004     0                 common
 // CHECK-NEXT: 0000000000000000 0000000000000008     1 .comment
 // CHECK-NEXT: 0000000000000000 0000000000000008     1         <internal>:(.comment)
-// CHECK-NEXT: 0000000000000000 00000000000000f0     8 .symtab
-// CHECK-NEXT: 0000000000000000 00000000000000f0     8         <internal>:(.symtab)
+// CHECK-NEXT: 0000000000000000 0000000000000120     8 .symtab
+// CHECK-NEXT: 0000000000000000 0000000000000120     8         <internal>:(.symtab)
 // CHECK-NEXT: 0000000000000000 0000000000000039     1 .shstrtab
 // CHECK-NEXT: 0000000000000000 0000000000000039     1         <internal>:(.shstrtab)
-// CHECK-NEXT: 0000000000000000 000000000000002f     1 .strtab
-// CHECK-NEXT: 0000000000000000 000000000000002f     1         <internal>:(.strtab)
+// CHECK-NEXT: 0000000000000000 0000000000000038     1 .strtab
+// CHECK-NEXT: 0000000000000000 0000000000000038     1         <internal>:(.strtab)
 
 // RUN: not ld.lld %t1.o %t2.o %t3.o %t4.a -o %t -Map=/ 2>&1 \
 // RUN:  | FileCheck -check-prefix=FAIL %s