diff --git a/intTests/test_issue521/ptr.bc b/intTests/test_issue521/ptr.bc
new file mode 100644
index 0000000000..1ecc22bfb8
Binary files /dev/null and b/intTests/test_issue521/ptr.bc differ
diff --git a/intTests/test_issue521/ptr.c b/intTests/test_issue521/ptr.c
new file mode 100644
index 0000000000..c7f42609cd
--- /dev/null
+++ b/intTests/test_issue521/ptr.c
@@ -0,0 +1,3 @@
+unsigned int add(unsigned int *x, unsigned int *y) {
+    return *x + *y;
+}
diff --git a/intTests/test_issue521/test.saw b/intTests/test_issue521/test.saw
new file mode 100644
index 0000000000..6e0aea0a93
--- /dev/null
+++ b/intTests/test_issue521/test.saw
@@ -0,0 +1,2 @@
+m <- llvm_load_module "ptr.bc";
+fails (crucible_llvm_extract m "add");
diff --git a/intTests/test_issue521/test.sh b/intTests/test_issue521/test.sh
new file mode 100644
index 0000000000..2315cc233c
--- /dev/null
+++ b/intTests/test_issue521/test.sh
@@ -0,0 +1,3 @@
+set -e
+
+$SAW test.saw
diff --git a/src/SAWScript/Crucible/LLVM/Builtins.hs b/src/SAWScript/Crucible/LLVM/Builtins.hs
index f658e5d287..d49b771795 100644
--- a/src/SAWScript/Crucible/LLVM/Builtins.hs
+++ b/src/SAWScript/Crucible/LLVM/Builtins.hs
@@ -64,7 +64,7 @@ import           Control.Monad.State hiding (fail)
 import           Control.Monad.Fail (MonadFail(..))
 import qualified Data.Bimap as Bimap
 import           Data.Char (isDigit)
-import           Data.Foldable (for_, toList, find)
+import           Data.Foldable (for_, toList, find, fold)
 import           Data.Function
 import           Data.IORef
 import           Data.List
@@ -1103,6 +1103,17 @@ crucible_llvm_extract ::
 crucible_llvm_extract bic opts (Some lm) fn_name = do
   let ctx = lm ^. modTrans . Crucible.transContext
   let ?lc = ctx^.Crucible.llvmTypeCtx
+  let edef = findDefMaybeStatic (lm ^. modAST) fn_name
+  case edef of
+    Right defs -> do
+      let defTypes = fold $
+                     NE.map (map L.typedType . L.defArgs) defs <>
+                     NE.map (\d -> [L.defRetType d]) defs
+      when (any L.isPointer defTypes) $
+        fail "Pointer types are not supported by `crucible_llvm_extract`."
+      when (any L.isAlias defTypes) $
+        fail "Type aliases are not supported by `crucible_llvm_extract`."
+    Left err -> fail (displayVerifExceptionOpts opts err)
   setupLLVMCrucibleContext bic opts lm $ \cc ->
     case Map.lookup (fromString fn_name) (Crucible.cfgMap (cc^.ccLLVMModuleTrans)) of
       Nothing  -> fail $ unwords ["function", fn_name, "not found"]