diff --git a/llvm/lib/Transforms/IPO/AlwaysInliner.cpp b/llvm/lib/Transforms/IPO/AlwaysInliner.cpp
--- a/llvm/lib/Transforms/IPO/AlwaysInliner.cpp
+++ b/llvm/lib/Transforms/IPO/AlwaysInliner.cpp
@@ -80,13 +80,18 @@
 
         InlineFunctionInfo IFI(
             /*cg=*/nullptr, GetAssumptionCache, &PSI,
-            &FAM.getResult<BlockFrequencyAnalysis>(*(CB->getCaller())),
+            &FAM.getResult<BlockFrequencyAnalysis>(*Caller),
             &FAM.getResult<BlockFrequencyAnalysis>(F));
 
         InlineResult Res = InlineFunction(
             *CB, IFI, &FAM.getResult<AAManager>(F), InsertLifetime);
-        assert(Res.isSuccess() && "unexpected failure to inline");
-        (void)Res;
+        if (!Res.isSuccess()) {
+          llvm::errs() << "Unable to inline " << F.getName() << " at "
+                       << Caller->getName() << ": " << Res.getFailureReason()
+                       << "\n";
+          assert(false && "unexpected failure to inline");
+          continue;
+        }
 
         // Merge the attributes based on the inlining.
         AttributeFuncs::mergeAttributesForInlining(*Caller, F);