document some invariants.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77084 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 1 deletions

diff --git a/lib/Target/TargetAsmInfo.cpp b/lib/Target/TargetAsmInfo.cpp
index 727c584e3a..dfb274f608 100644
--- a/lib/Target/TargetAsmInfo.cpp
+++ b/lib/Target/TargetAsmInfo.cpp
@@ -293,8 +293,13 @@ static SectionKind::Kind SectionKindForGlobal(const GlobalValue *GV,
   }
 }
 
-
+/// SectionForGlobal - This method computes the appropriate section to emit
+/// the specified global variable or function definition.  This should not
+/// be passed external (or available externally) globals.
 const Section *TargetAsmInfo::SectionForGlobal(const GlobalValue *GV) const {
+  assert(!GV->isDeclaration() && !GV->hasAvailableExternallyLinkage() &&
+         "Can only be used for global definitions");
+  
   SectionKind::Kind Kind = SectionKindForGlobal(GV, TM.getRelocationModel());
 
   // Select section name.