Return a StringRef from getSection.

This is similar to how getName is handled.

llvm-svn: 269218
diff --git a/llvm/lib/IR/Core.cpp b/llvm/lib/IR/Core.cpp
index d69e8d5..0c6c6f5 100644
--- a/llvm/lib/IR/Core.cpp
+++ b/llvm/lib/IR/Core.cpp
@@ -1485,7 +1485,9 @@
 }
 
 const char *LLVMGetSection(LLVMValueRef Global) {
-  return unwrap<GlobalValue>(Global)->getSection();
+  // Using .data() is safe because of how GlobalObject::setSection is
+  // implemented.
+  return unwrap<GlobalValue>(Global)->getSection().data();
 }
 
 void LLVMSetSection(LLVMValueRef Global, const char *Section) {
diff --git a/llvm/lib/IR/Globals.cpp b/llvm/lib/IR/Globals.cpp
index a9702b7..7e8ef65 100644
--- a/llvm/lib/IR/Globals.cpp
+++ b/llvm/lib/IR/Globals.cpp
@@ -128,7 +128,7 @@
                              getParent()->getSourceFileName());
 }
 
-const char *GlobalValue::getSection() const {
+StringRef GlobalValue::getSection() const {
   if (auto *GA = dyn_cast<GlobalAlias>(this)) {
     // In general we cannot compute this at the IR level, but we try.
     if (const GlobalObject *GO = GA->getBaseObject())
@@ -151,7 +151,12 @@
   return cast<GlobalObject>(this)->getComdat();
 }
 
-void GlobalObject::setSection(StringRef S) { Section = S; }
+void GlobalObject::setSection(StringRef S) {
+  Section = S;
+
+  // The C api requires this to be null terminated.
+  Section.c_str();
+}
 
 bool GlobalValue::isDeclaration() const {
   // Globals are definitions if they have an initializer.