diff --git a/test/printf-test.cc b/test/printf-test.cc
index 3e22d467..74a6bd2c 100644
--- a/test/printf-test.cc
+++ b/test/printf-test.cc
@@ -38,7 +38,7 @@ using fmt::FormatError;
 // Returns a number UINT_MAX + 1 formatted as a string.
 std::string GetBigNumber() {
   char format[BUFFER_SIZE];
-  sprintf(format, "%u", UINT_MAX);
+  SPrintf(format, "%u", UINT_MAX);
   Increment(format + 1);
   return format;
 }
diff --git a/test/util-test.cc b/test/util-test.cc
index becd9ff1..af78cd16 100644
--- a/test/util-test.cc
+++ b/test/util-test.cc
@@ -239,7 +239,7 @@ TEST(UtilTest, FormatWinErrorMessage) {
   fmt::internal::FormatWinErrorMessage(
       actual_message, ERROR_FILE_EXISTS, "test");
   EXPECT_EQ(fmt::format("test: {}", fmt::str(utf8_message)),
-      fmt::str(actual_message));
+      actual_message.str());
 }
 
 TEST(UtilTest, WinErrorSink) {