[llvm-commits] [llvm] r51207 - /llvm/trunk/lib/Transforms/IPO/PruneEH.cpp

[Dale Johannesen]

Author: johannes
Date: Fri May 16 16:31:48 2008
New Revision: 51207

URL: http://llvm.org/viewvc/llvm-project?rev=51207&view=rev
Log:
Weak functions not declared non-throwing might be
replaced at linktime with a body that throws, even
if the body in this file does not.  Make PruneEH
be more conservative in this case.
g++.dg/eh/weak1.C


Modified:
    llvm/trunk/lib/Transforms/IPO/PruneEH.cpp

Modified: llvm/trunk/lib/Transforms/IPO/PruneEH.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/PruneEH.cpp?rev=51207&r1=51206&r2=51207&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/IPO/PruneEH.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/PruneEH.cpp Fri May 16 16:31:48 2008
@@ -64,6 +64,8 @@
 
   // Next, check to see if any callees might throw or if there are any external
   // functions in this SCC: if so, we cannot prune any functions in this SCC.
+  // Definitions that are weak and not declared non-throwing might be 
+  // overridden at linktime with something that throws, so assume that.
   // If this SCC includes the unwind instruction, we KNOW it throws, so
   // obviously the SCC might throw.
   //
@@ -71,7 +73,7 @@
   for (unsigned i = 0, e = SCC.size();
        (!SCCMightUnwind || !SCCMightReturn) && i != e; ++i) {
     Function *F = SCC[i]->getFunction();
-    if (F == 0) {
+    if (F == 0 || (F->hasWeakLinkage() && !F->doesNotThrow())) {
       SCCMightUnwind = true;
       SCCMightReturn = true;
     } else if (F->isDeclaration()) {