From 078c963a310048f84d1d74d7ed09fd610238d87a Mon Sep 17 00:00:00 2001
From: Eli Friedman <eli.friedman@gmail.com>
Date: Tue, 27 May 2008 04:58:01 +0000
Subject: [PATCH] Add a more reliable check for whether a static declaration
 has already been used.  In preparation for the fix to PR2360, but also a
 minor bug in its own right.

llvm-svn: 51583
---
 clang/lib/CodeGen/CodeGenModule.cpp      | 29 ++++++++++--------------
 clang/test/CodeGen/static-forward-decl.c |  5 ++++
 2 files changed, 17 insertions(+), 17 deletions(-)
 create mode 100644 clang/test/CodeGen/static-forward-decl.c

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 329599c1166b..f14a0858d303 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -341,19 +341,6 @@ void CodeGenModule::EmitFunction(const FunctionDecl *FD) {
     CodeGenFunction(*this).GenerateCode(FD);
     return;
   }
-      
-  // We need to check the Module here to see if GetAddrOfFunctionDecl() has
-  // already added this function to the Module because the address of the
-  // function's prototype was taken.  If this is the case, call 
-  // GetAddrOfFunctionDecl to insert the static FunctionDecl into the used
-  // GlobalDeclsMap, so that EmitStatics will generate code for it later.
-  //
-  // Example:
-  // static int foo();
-  // int bar() { return foo(); }
-  // static int foo() { return 5; }
-  if (getModule().getFunction(FD->getName()))
-    GetAddrOfFunctionDecl(FD, true);
 
   StaticDecls.push_back(FD);
 }
@@ -366,11 +353,19 @@ void CodeGenModule::EmitStatics() {
   do {
     Changed = false;
     for (unsigned i = 0, e = StaticDecls.size(); i != e; ++i) {
-      // Check the map of used decls for our static. If not found, continue.
       const Decl *D = StaticDecls[i];
-      if (!GlobalDeclMap.count(D))
-        continue;
-      
+
+      // Check if we have used a decl with the same name
+      // FIXME: The AST should have some sort of aggregate decls or
+      // global symbol map.
+      if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
+        if (!getModule().getFunction(FD->getName()))
+          continue;
+      } else {
+        if (!getModule().getNamedGlobal(cast<VarDecl>(D)->getName()))
+          continue;
+      }
+
       // If this is a function decl, generate code for the static function if it
       // has a body.  Otherwise, we must have a var decl for a static global
       // variable.
diff --git a/clang/test/CodeGen/static-forward-decl.c b/clang/test/CodeGen/static-forward-decl.c
new file mode 100644
index 000000000000..8e0825cb6c82
--- /dev/null
+++ b/clang/test/CodeGen/static-forward-decl.c
@@ -0,0 +1,5 @@
+// RUN: clang %s -emit-llvm -o - -triple=i686-apple-darwin9 | grep "global i32 10"
+
+static int i;
+int*j=&i;
+static int i = 10;