diff --git a/change_notes/2024-07-23-fix-fp-646-M0-1-10.md b/change_notes/2024-07-23-fix-fp-646-M0-1-10.md
new file mode 100644
index 0000000000..8854c7b59a
--- /dev/null
+++ b/change_notes/2024-07-23-fix-fp-646-M0-1-10.md
@@ -0,0 +1,2 @@
+- `M0-1-10` - `EncapsulatingFunctions.qll`:
+  - Fixes #646. Consider typedef'd `int` return types for `main()` function as MainFunction.
diff --git a/cpp/autosar/test/rules/M0-1-10.1/UnusedFunction.expected b/cpp/autosar/test/rules/M0-1-10.1/UnusedFunction.expected
new file mode 100644
index 0000000000..3f58065520
--- /dev/null
+++ b/cpp/autosar/test/rules/M0-1-10.1/UnusedFunction.expected
@@ -0,0 +1 @@
+| test.cpp:23:14:23:26 | uncalled_func | Function uncalled_func is never called. |
diff --git a/cpp/autosar/test/rules/M0-1-10.1/UnusedFunction.qlref b/cpp/autosar/test/rules/M0-1-10.1/UnusedFunction.qlref
new file mode 100644
index 0000000000..519660f289
--- /dev/null
+++ b/cpp/autosar/test/rules/M0-1-10.1/UnusedFunction.qlref
@@ -0,0 +1 @@
+rules/M0-1-10/UnusedFunction.ql
\ No newline at end of file
diff --git a/cpp/autosar/test/rules/M0-1-10.1/test.cpp b/cpp/autosar/test/rules/M0-1-10.1/test.cpp
new file mode 100644
index 0000000000..5b9c68a827
--- /dev/null
+++ b/cpp/autosar/test/rules/M0-1-10.1/test.cpp
@@ -0,0 +1,39 @@
+#include <cstdint>
+
+namespace mains {
+static std::int32_t var;
+
+// @brief namespace_func
+static void
+namespace_func(void) noexcept { // COMPLIANT: Called from "main" below.
+  mains::var = -1;
+  return;
+}
+} // namespace mains
+
+std::int32_t func2() // COMPLIANT: Called from func1
+{
+  return mains::var + 20;
+}
+
+std::int32_t func1() {         // COMPLIANT: Called from main
+  return mains::var + func2(); // func2 called here.
+}
+
+std::int32_t uncalled_func() // NON_COMPLIANT: Not called.
+{
+  return mains::var + func1(); // func1 called here.
+}
+
+// @brief main
+// @return exit code
+std::int32_t main(void) {
+  std::int32_t ret{0};
+  try {
+    ret = func1(); // func1 called here.
+    mains::var += ret;
+  } catch (...) {
+    mains::namespace_func(); // namespace_func called here.
+  }
+  return ret;
+}
diff --git a/cpp/common/src/codingstandards/cpp/EncapsulatingFunctions.qll b/cpp/common/src/codingstandards/cpp/EncapsulatingFunctions.qll
index d8d9739033..f82705e2c7 100644
--- a/cpp/common/src/codingstandards/cpp/EncapsulatingFunctions.qll
+++ b/cpp/common/src/codingstandards/cpp/EncapsulatingFunctions.qll
@@ -14,7 +14,7 @@ abstract class EncapsulatingFunction extends Function { }
 class MainFunction extends MainLikeFunction {
   MainFunction() {
     hasGlobalName("main") and
-    getType() instanceof IntType
+    getType().resolveTypedefs() instanceof IntType
   }
 }
 
diff --git a/cpp/common/test/library/codingstandards/cpp/mainlikefunctions/typedefint/MainLikeFunction.expected b/cpp/common/test/library/codingstandards/cpp/mainlikefunctions/typedefint/MainLikeFunction.expected
new file mode 100644
index 0000000000..fa98ca7648
--- /dev/null
+++ b/cpp/common/test/library/codingstandards/cpp/mainlikefunctions/typedefint/MainLikeFunction.expected
@@ -0,0 +1 @@
+| test.cpp:5:9:5:12 | main |
diff --git a/cpp/common/test/library/codingstandards/cpp/mainlikefunctions/typedefint/MainLikeFunction.ql b/cpp/common/test/library/codingstandards/cpp/mainlikefunctions/typedefint/MainLikeFunction.ql
new file mode 100644
index 0000000000..ed1757631e
--- /dev/null
+++ b/cpp/common/test/library/codingstandards/cpp/mainlikefunctions/typedefint/MainLikeFunction.ql
@@ -0,0 +1,5 @@
+import cpp
+import codingstandards.cpp.EncapsulatingFunctions
+
+from MainFunction m
+select m
diff --git a/cpp/common/test/library/codingstandards/cpp/mainlikefunctions/typedefint/test.cpp b/cpp/common/test/library/codingstandards/cpp/mainlikefunctions/typedefint/test.cpp
new file mode 100644
index 0000000000..7b514505f1
--- /dev/null
+++ b/cpp/common/test/library/codingstandards/cpp/mainlikefunctions/typedefint/test.cpp
@@ -0,0 +1,8 @@
+typedef signed int int32_t;
+
+// @brief main
+// @return exit code
+int32_t main(void) {
+  int32_t ret{0};
+  return ret;
+}