diff --git a/base-test/org.eclipse.jdt.groovy.core.tests.compiler/src/org/eclipse/jdt/groovy/core/tests/xform/StaticCompilationTests.java b/base-test/org.eclipse.jdt.groovy.core.tests.compiler/src/org/eclipse/jdt/groovy/core/tests/xform/StaticCompilationTests.java
index e0f4746f37..1556886306 100644
--- a/base-test/org.eclipse.jdt.groovy.core.tests.compiler/src/org/eclipse/jdt/groovy/core/tests/xform/StaticCompilationTests.java
+++ b/base-test/org.eclipse.jdt.groovy.core.tests.compiler/src/org/eclipse/jdt/groovy/core/tests/xform/StaticCompilationTests.java
@@ -6288,6 +6288,9 @@ public void testCompileStatic10072() {
             "  c = { p, q = 'baz' -> '' + p + q }\n" +
             "  assert c('foo', 'bar') == 'foobar'\n" +
             "  assert c('foo') == 'foobaz'\n" +
+            "  c = { p, q = p.toString() -> '' + p + q }\n" +
+            "  assert c('foo', 'bar') == 'foobar'\n" +
+            "  assert c('foo') == 'foofoo'\n" +
             "}\n" +
             "test()\n",
         };
diff --git a/base-test/org.eclipse.jdt.groovy.core.tests.compiler/src/org/eclipse/jdt/groovy/core/tests/xform/TypeCheckedTests.java b/base-test/org.eclipse.jdt.groovy.core.tests.compiler/src/org/eclipse/jdt/groovy/core/tests/xform/TypeCheckedTests.java
index 20a311f195..3ddec80e99 100644
--- a/base-test/org.eclipse.jdt.groovy.core.tests.compiler/src/org/eclipse/jdt/groovy/core/tests/xform/TypeCheckedTests.java
+++ b/base-test/org.eclipse.jdt.groovy.core.tests.compiler/src/org/eclipse/jdt/groovy/core/tests/xform/TypeCheckedTests.java
@@ -3000,6 +3000,26 @@ public void testTypeChecked10091() {
             "----------\n");
     }
 
+    @Test
+    public void testTypeChecked10094() {
+        //@formatter:off
+        String[] sources = {
+            "Main.groovy",
+            "@groovy.transform.TypeChecked\n" +
+            "void test(int i = 'error') {}\n" +
+            "test()\n",
+        };
+        //@formatter:on
+
+        runNegativeTest(sources,
+            "----------\n" +
+            "1. ERROR in Main.groovy (at line 2)\n" +
+            "\tvoid test(int i = 'error') {}\n" +
+            "\t                  ^^^^^^^\n" +
+            "Groovy:[Static type checking] - Cannot assign value of type java.lang.String to variable of type int\n" +
+            "----------\n");
+    }
+
     @Test
     public void testTypeChecked10098() {
         //@formatter:off
diff --git a/base/org.codehaus.groovy25/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java b/base/org.codehaus.groovy25/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java
index 5693db2a49..14b4dc1c5f 100644
--- a/base/org.codehaus.groovy25/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java
+++ b/base/org.codehaus.groovy25/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java
@@ -36,6 +36,7 @@
 import org.codehaus.groovy.ast.ClassCodeVisitorSupport;
 import org.codehaus.groovy.ast.ClassHelper;
 import org.codehaus.groovy.ast.ClassNode;
+import org.codehaus.groovy.ast.CodeVisitorSupport;
 import org.codehaus.groovy.ast.ConstructorNode;
 import org.codehaus.groovy.ast.DynamicVariable;
 import org.codehaus.groovy.ast.FieldNode;
@@ -2611,6 +2612,21 @@ protected void visitConstructorOrMethod(MethodNode node, boolean isConstructor)
         typeCheckingContext.pushEnclosingMethod(node);
         if (!isSkipMode(node) && !shouldSkipMethodNode(node)) {
             super.visitConstructorOrMethod(node, isConstructor);
+            // GRECLIPSE add
+            if (node.hasDefaultValue())
+            for (Parameter parameter : node.getParameters()) {
+                if (!parameter.hasInitialExpression()) continue;
+                // GROOVY-10094: visit param default argument expression
+                visitInitialExpression(parameter.getInitialExpression(), varX(parameter), parameter);
+                // GROOVY-10104: remove direct target setting to prevent errors
+                parameter.getInitialExpression().visit(new CodeVisitorSupport() {
+                    @Override
+                    public void visitMethodCallExpression(final MethodCallExpression mce) {
+                        mce.setMethodTarget(null); super.visitMethodCallExpression(mce);
+                    }
+                });
+            }
+            // GRECLIPSE end
         }
         if (!isConstructor) {
             returnAdder.visitMethod(node); // return statement added after visitConstructorOrMethod finished... we can not count these auto-generated return statements(GROOVY-7753), see `typeCheckingContext.pushEnclosingReturnStatement`
diff --git a/base/org.codehaus.groovy30/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java b/base/org.codehaus.groovy30/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java
index 1aa145f8be..830330eb2e 100644
--- a/base/org.codehaus.groovy30/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java
+++ b/base/org.codehaus.groovy30/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java
@@ -36,6 +36,7 @@
 import org.codehaus.groovy.ast.ClassCodeVisitorSupport;
 import org.codehaus.groovy.ast.ClassHelper;
 import org.codehaus.groovy.ast.ClassNode;
+import org.codehaus.groovy.ast.CodeVisitorSupport;
 import org.codehaus.groovy.ast.ConstructorNode;
 import org.codehaus.groovy.ast.DynamicVariable;
 import org.codehaus.groovy.ast.FieldNode;
@@ -2344,6 +2345,21 @@ protected void visitConstructorOrMethod(final MethodNode node, final boolean isC
         typeCheckingContext.pushEnclosingMethod(node);
         if (!isSkipMode(node) && !shouldSkipMethodNode(node)) {
             super.visitConstructorOrMethod(node, isConstructor);
+            // GRECLIPSE add
+            if (node.hasDefaultValue())
+            for (Parameter parameter : node.getParameters()) {
+                if (!parameter.hasInitialExpression()) continue;
+                // GROOVY-10094: visit param default argument expression
+                visitInitialExpression(parameter.getInitialExpression(), varX(parameter), parameter);
+                // GROOVY-10104: remove direct target setting to prevent errors
+                parameter.getInitialExpression().visit(new CodeVisitorSupport() {
+                    @Override
+                    public void visitMethodCallExpression(final MethodCallExpression mce) {
+                        mce.setMethodTarget(null); super.visitMethodCallExpression(mce);
+                    }
+                });
+            }
+            // GRECLIPSE end
         }
         if (!isConstructor) {
             returnAdder.visitMethod(node); // return statement added after visitConstructorOrMethod finished... we can not count these auto-generated return statements(GROOVY-7753), see `typeCheckingContext.pushEnclosingReturnStatement`
diff --git a/base/org.codehaus.groovy40/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java b/base/org.codehaus.groovy40/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java
index 3983157146..4d43304219 100644
--- a/base/org.codehaus.groovy40/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java
+++ b/base/org.codehaus.groovy40/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java
@@ -2176,6 +2176,21 @@ protected void visitConstructorOrMethod(final MethodNode node, final boolean isC
         typeCheckingContext.pushEnclosingMethod(node);
         if (!isSkipMode(node) && !shouldSkipMethodNode(node)) {
             super.visitConstructorOrMethod(node, isConstructor);
+            // GRECLIPSE add
+            if (node.hasDefaultValue())
+            for (Parameter parameter : node.getParameters()) {
+                if (!parameter.hasInitialExpression()) continue;
+                // GROOVY-10094: visit param default argument expression
+                visitInitialExpression(parameter.getInitialExpression(), varX(parameter), parameter);
+                // GROOVY-10104: remove direct target setting to prevent errors
+                parameter.getInitialExpression().visit(new CodeVisitorSupport() {
+                    @Override
+                    public void visitMethodCallExpression(final MethodCallExpression mce) {
+                        mce.setMethodTarget(null); super.visitMethodCallExpression(mce);
+                    }
+                });
+            }
+            // GRECLIPSE end
         }
         if (!isConstructor) {
             returnAdder.visitMethod(node); // return statement added after visitConstructorOrMethod finished... we can not count these auto-generated return statements(GROOVY-7753), see `typeCheckingContext.pushEnclosingReturnStatement`