diff --git a/pxr/usd/sdf/testenv/testSdfAttributeBlocking.cpp b/pxr/usd/sdf/testenv/testSdfAttributeBlocking.cpp
index 6c7675343d..99b850634a 100644
--- a/pxr/usd/sdf/testenv/testSdfAttributeBlocking.cpp
+++ b/pxr/usd/sdf/testenv/testSdfAttributeBlocking.cpp
@@ -113,4 +113,5 @@ int main(int argc, char** argv) {
     layer->GetFieldAs<SdfValueBlock>(defAttr->GetPath(), SdfFieldKeys->Default);
 
     printf(">>> Test SUCCEEDED\n");
+    return 0;
 }
diff --git a/pxr/usd/usd/testenv/testUsdAttributeBlocking.cpp b/pxr/usd/usd/testenv/testUsdAttributeBlocking.cpp
index e8de695cf9..cfdb93af14 100644
--- a/pxr/usd/usd/testenv/testUsdAttributeBlocking.cpp
+++ b/pxr/usd/usd/testenv/testUsdAttributeBlocking.cpp
@@ -257,4 +257,5 @@ int main(int argc, char** argv) {
     }
 
     printf("\n\n>>> Test SUCCEEDED\n");
+    return 0;
 }