2 files changed, 12 insertions, 2 deletions
diff --git a/src/tools/wasm-dis.cpp b/src/tools/wasm-dis.cpp
index e8ca71528..f9f303359 100644
--- a/src/tools/wasm-dis.cpp
+++ b/src/tools/wasm-dis.cpp
@@ -70,7 +70,12 @@ int main(int argc, const char* argv[]) {
   } catch (ParseException& p) {
     p.dump(std::cerr);
     std::cerr << '\n';
-    Fatal() << "error in parsing wasm binary";
+    if (options.debug) {
+      Fatal() << "error parsing wasm. here is what we read up to the error:\n"
+              << wasm;
+    } else {
+      Fatal() << "error parsing wasm (try --debug for more info)";
+    }
   } catch (MapParseException& p) {
     p.dump(std::cerr);
     std::cerr << '\n';
diff --git a/src/tools/wasm-opt.cpp b/src/tools/wasm-opt.cpp
index effd085bc..8f958f164 100644
--- a/src/tools/wasm-opt.cpp
+++ b/src/tools/wasm-opt.cpp
@@ -279,7 +279,12 @@ int main(int argc, const char* argv[]) {
     } catch (ParseException& p) {
       p.dump(std::cerr);
       std::cerr << '\n';
-      Fatal() << "error parsing wasm";
+      if (options.debug) {
+        Fatal() << "error parsing wasm. here is what we read up to the error:\n"
+                << wasm;
+      } else {
+        Fatal() << "error parsing wasm (try --debug for more info)";
+      }
     } catch (MapParseException& p) {
       p.dump(std::cerr);
       std::cerr << '\n';