diff --git a/Process.cpp b/Process.cpp
index 042ba2d..9038af2 100644
--- a/Process.cpp
+++ b/Process.cpp
@@ -52,7 +52,7 @@ static bool checkMaps(const std::string& path, const std::string& prefix) {
         std::string::size_type pos = line.find('/');
         if (pos != std::string::npos) {
             line = line.substr(pos);
-            if (android::base::StartsWith(line, prefix.c_str())) {
+            if (android::base::StartsWith(line, prefix)) {
                 LOG(WARNING) << "Found map " << path << " referencing " << line;
                 found = true;
             }
@@ -64,7 +64,7 @@ static bool checkMaps(const std::string& path, const std::string& prefix) {
 static bool checkSymlink(const std::string& path, const std::string& prefix) {
     std::string res;
     if (android::base::Readlink(path, &res)) {
-        if (android::base::StartsWith(res, prefix.c_str())) {
+        if (android::base::StartsWith(res, prefix)) {
             LOG(WARNING) << "Found symlink " << path << " referencing " << res;
             return true;
         }
diff --git a/VolumeManager.cpp b/VolumeManager.cpp
index 0936ed0..5e6e74f 100644
--- a/VolumeManager.cpp
+++ b/VolumeManager.cpp
@@ -426,7 +426,7 @@ static int unmount_tree(const std::string& prefix) {
     mntent* mentry;
     while ((mentry = getmntent(fp)) != NULL) {
         auto test = std::string(mentry->mnt_dir) + "/";
-        if (android::base::StartsWith(test, prefix.c_str())) {
+        if (android::base::StartsWith(test, prefix)) {
             toUnmount.push_front(test);
         }
     }