[lld] r316622 - Unassign sections if they are "assigned" to /DISCARD/.

[Rui Ueyama via llvm-commits]

Author: ruiu
Date: Wed Oct 25 15:03:21 2017
New Revision: 316622

URL: http://llvm.org/viewvc/llvm-project?rev=316622&view=rev
Log:
Unassign sections if they are "assigned" to /DISCARD/.

"/DISCARD/" is a special section name in the linker script to discard
input sections. Previously, we handled it as if it were a real section,
so an input section can be assigned but dead. However, allowing sections
to be

 - assigned and alive (will be emitted),
 - not assigned and dead (removed), or
 - assigned but dead (???)

feels logically wrong and practically error-prone. This patch removes
the last combination of the states.

Modified:
    lld/trunk/ELF/LinkerScript.cpp

Modified: lld/trunk/ELF/LinkerScript.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/LinkerScript.cpp?rev=316622&r1=316621&r2=316622&view=diff
==============================================================================
--- lld/trunk/ELF/LinkerScript.cpp (original)
+++ lld/trunk/ELF/LinkerScript.cpp Wed Oct 25 15:03:21 2017
@@ -318,10 +318,12 @@ LinkerScript::computeInputSections(const
 
 void LinkerScript::discard(ArrayRef<InputSection *> V) {
   for (InputSection *S : V) {
-    S->Live = false;
     if (S == InX::ShStrTab || S == InX::Dynamic || S == InX::DynSymTab ||
         S == InX::DynStrTab)
       error("discarding " + S->Name + " section is not allowed");
+
+    S->Assigned = false;
+    S->Live = false;
     discard(S->DependentSections);
   }
 }