Add tuple.drop validation (#6186)

Without this fuzzer testcases fail if the initial content has a tuple.drop but multivalue
is disabled (then the initial content validates erroneously, and that content is remixed
into more content using multivalue which fails to validate).

1 files changed, 5 insertions, 0 deletions

diff --git a/src/wasm/wasm-validator.cpp b/src/wasm/wasm-validator.cpp
index c1b4a86e7..8c165b700 100644
--- a/src/wasm/wasm-validator.cpp
+++ b/src/wasm/wasm-validator.cpp
@@ -2123,6 +2123,11 @@ void FunctionValidator::visitDrop(Drop* curr) {
                  curr->value->type == Type::unreachable,
                curr,
                "can only drop a valid value");
+  if (curr->value->type.isTuple()) {
+    shouldBeTrue(getModule()->features.hasMultivalue(),
+                 curr,
+                 "Tuples drops are not allowed unless multivalue is enabled");
+  }
 }
 
 void FunctionValidator::visitReturn(Return* curr) {