diff --git a/src/compiler-support.h b/src/compiler-support.h
index a3485919086..3082ab3dfa1 100644
--- a/src/compiler-support.h
+++ b/src/compiler-support.h
@@ -31,4 +31,10 @@
 #define WASM_BUILTIN_UNREACHABLE __assume(false)
 #endif
 
+#if defined(__GNUC__) || defined(__clang__)
+#define BYN_WARN_UNUSED [[gnu::warn_unused]]
+#else
+#define BYN_WARN_UNUSED
+#endif
+
 #endif // wasm_compiler_support_h
diff --git a/src/ir/possible-contents.cpp b/src/ir/possible-contents.cpp
index f5bdb46fc09..f752fa10172 100644
--- a/src/ir/possible-contents.cpp
+++ b/src/ir/possible-contents.cpp
@@ -898,7 +898,6 @@ struct InfoCollector
   }
 
   void visitCall(Call* curr) {
-    Name targetName;
     if (!Intrinsics(*getModule()).isCallWithoutEffects(curr)) {
       // This is just a normal call.
       handleDirectCall(curr, curr->target);
diff --git a/src/support/istring.h b/src/support/istring.h
index bc7d2380dd2..458c8b47c6e 100644
--- a/src/support/istring.h
+++ b/src/support/istring.h
@@ -31,7 +31,7 @@
 
 namespace wasm {
 
-struct IString {
+struct BYN_WARN_UNUSED IString {
 private:
   static const char* interned(std::string_view s);
 
diff --git a/src/support/name.h b/src/support/name.h
index d6c71f732c9..2d22f8ad1cb 100644
--- a/src/support/name.h
+++ b/src/support/name.h
@@ -31,7 +31,7 @@ namespace wasm {
 // TODO: as an optimization, IString values < some threshold could be considered
 //       numerical indices directly.
 
-struct Name : public IString {
+struct BYN_WARN_UNUSED Name : public IString {
   Name() : IString() {}
   Name(std::string_view str) : IString(str) {}
   Name(const char* str) : IString(str) {}
diff --git a/src/tools/wasm-ctor-eval.cpp b/src/tools/wasm-ctor-eval.cpp
index 42cd1097623..f5b05c98220 100644
--- a/src/tools/wasm-ctor-eval.cpp
+++ b/src/tools/wasm-ctor-eval.cpp
@@ -1540,8 +1540,6 @@ static bool canEval(Module& wasm) {
 //
 
 int main(int argc, const char* argv[]) {
-  Name entry;
-  std::vector<std::string> passes;
   bool emitBinary = true;
   bool debugInfo = false;
   String::Split ctors;
diff --git a/src/tools/wasm-metadce.cpp b/src/tools/wasm-metadce.cpp
index f0647a4c337..3f7c44cc5d4 100644
--- a/src/tools/wasm-metadce.cpp
+++ b/src/tools/wasm-metadce.cpp
@@ -416,8 +416,6 @@ struct MetaDCEGraph {
 //
 
 int main(int argc, const char* argv[]) {
-  Name entry;
-  std::vector<std::string> passes;
   bool emitBinary = true;
   bool debugInfo = false;
   std::string graphFile;
diff --git a/src/tools/wasm-opt.cpp b/src/tools/wasm-opt.cpp
index ef85804963c..94d72181cac 100644
--- a/src/tools/wasm-opt.cpp
+++ b/src/tools/wasm-opt.cpp
@@ -74,7 +74,6 @@ willRemoveDebugInfo(const std::vector<OptimizationOptions::PassInfo>& passes) {
 //
 
 int main(int argc, const char* argv[]) {
-  Name entry;
   bool emitBinary = true;
   bool converge = false;
   bool fuzzExecBefore = false;
diff --git a/src/tools/wasm-shell.cpp b/src/tools/wasm-shell.cpp
index ca864998714..e33400320af 100644
--- a/src/tools/wasm-shell.cpp
+++ b/src/tools/wasm-shell.cpp
@@ -655,9 +655,6 @@ struct Shell {
 };
 
 int main(int argc, const char* argv[]) {
-  Name entry;
-  std::set<size_t> skipped;
-
   // Read stdin by default.
   std::string infile = "-";
   Options options("wasm-shell", "Execute .wast files");