diff --git a/src/main/native/cpp/support/HttpUtil.cpp b/src/main/native/cpp/support/HttpUtil.cpp
index a7fac57884..8b84c0b468 100644
--- a/src/main/native/cpp/support/HttpUtil.cpp
+++ b/src/main/native/cpp/support/HttpUtil.cpp
@@ -17,10 +17,12 @@
 
 namespace wpi {
 
-llvm::StringRef UnescapeURI(llvm::StringRef str,
+llvm::StringRef UnescapeURI(const llvm::Twine& str,
                             llvm::SmallVectorImpl<char>& buf, bool* error) {
+  llvm::SmallString<128> strBuf;
+  llvm::StringRef strStr = str.toStringRef(strBuf);
   buf.clear();
-  for (auto i = str.begin(), end = str.end(); i != end; ++i) {
+  for (auto i = strStr.begin(), end = strStr.end(); i != end; ++i) {
     // pass non-escaped characters to output
     if (*i != '%') {
       // decode + to space
@@ -55,12 +57,14 @@ llvm::StringRef UnescapeURI(llvm::StringRef str,
   return llvm::StringRef{buf.data(), buf.size()};
 }
 
-llvm::StringRef EscapeURI(llvm::StringRef str, llvm::SmallVectorImpl<char>& buf,
-                          bool spacePlus) {
+llvm::StringRef EscapeURI(const llvm::Twine& str,
+                          llvm::SmallVectorImpl<char>& buf, bool spacePlus) {
   static const char *const hexLut = "0123456789ABCDEF";
 
+  llvm::SmallString<128> strBuf;
+  llvm::StringRef strStr = str.toStringRef(strBuf);
   buf.clear();
-  for (auto i = str.begin(), end = str.end(); i != end; ++i) {
+  for (auto i = strStr.begin(), end = strStr.end(); i != end; ++i) {
     // pass unreserved characters to output
     if (std::isalnum(*i) || *i == '-' || *i == '_' || *i == '.' || *i == '~') {
       buf.push_back(*i);
@@ -168,11 +172,11 @@ bool FindMultipartBoundary(raw_istream& is, llvm::StringRef boundary,
   }
 }
 
-HttpLocation::HttpLocation(llvm::StringRef url_, bool* error,
+HttpLocation::HttpLocation(const llvm::Twine& url_, bool* error,
                            std::string* errorMsg)
-    : url{url_} {
+    : url{url_.str()} {
   // Split apart into components
-  llvm::StringRef query{url_};
+  llvm::StringRef query{url};
 
   // scheme:
   llvm::StringRef scheme;
diff --git a/src/main/native/cpp/support/raw_istream.cpp b/src/main/native/cpp/support/raw_istream.cpp
index 0ae7cf2868..e0e204a93e 100644
--- a/src/main/native/cpp/support/raw_istream.cpp
+++ b/src/main/native/cpp/support/raw_istream.cpp
@@ -65,11 +65,11 @@ void raw_mem_istream::read_impl(void* data, std::size_t len) {
   m_left -= len;
 }
 
-static int getFD(llvm::StringRef Filename, std::error_code &EC) {
+static int getFD(const llvm::Twine& Filename, std::error_code &EC) {
   // Handle "-" as stdin. Note that when we do this, we consider ourself
   // the owner of stdin. This means that we can do things like close the
   // file descriptor when we're done and set the "binary" flag globally.
-  if (Filename == "-") {
+  if (Filename.isSingleStringRef() && Filename.getSingleStringRef() == "-") {
     EC = std::error_code();
     return STDIN_FILENO;
   }
@@ -84,7 +84,7 @@ static int getFD(llvm::StringRef Filename, std::error_code &EC) {
   return FD;
 }
 
-raw_fd_istream::raw_fd_istream(llvm::StringRef filename, std::error_code& ec,
+raw_fd_istream::raw_fd_istream(const llvm::Twine& filename, std::error_code& ec,
                                std::size_t bufSize)
     : raw_fd_istream(getFD(filename, ec), true, bufSize) {}
 
diff --git a/src/main/native/include/support/HttpUtil.h b/src/main/native/include/support/HttpUtil.h
index b380cb1f49..f02c581131 100644
--- a/src/main/native/include/support/HttpUtil.h
+++ b/src/main/native/include/support/HttpUtil.h
@@ -16,6 +16,7 @@
 #include "llvm/SmallVector.h"
 #include "llvm/StringMap.h"
 #include "llvm/StringRef.h"
+#include "llvm/Twine.h"
 #include "support/raw_istream.h"
 #include "support/raw_socket_istream.h"
 #include "support/raw_socket_ostream.h"
@@ -27,14 +28,15 @@ namespace wpi {
 // @param buf Buffer for output
 // @param error Set to true if an error occurred
 // @return Escaped string
-llvm::StringRef UnescapeURI(llvm::StringRef str,
+llvm::StringRef UnescapeURI(const llvm::Twine& str,
                             llvm::SmallVectorImpl<char>& buf, bool* error);
 
 // Escape a string with %xx-encoding.
 // @param buf Buffer for output
 // @param spacePlus If true, encodes spaces to '+' rather than "%20"
 // @return Escaped string
-llvm::StringRef EscapeURI(llvm::StringRef str, llvm::SmallVectorImpl<char>& buf,
+llvm::StringRef EscapeURI(const llvm::Twine& str,
+                          llvm::SmallVectorImpl<char>& buf,
                           bool spacePlus = true);
 
 // Parse a set of HTTP headers.  Saves just the Content-Type and Content-Length
@@ -60,7 +62,7 @@ bool FindMultipartBoundary(wpi::raw_istream& is, llvm::StringRef boundary,
 class HttpLocation {
  public:
   HttpLocation() = default;
-  HttpLocation(llvm::StringRef url_, bool* error, std::string* errorMsg);
+  HttpLocation(const llvm::Twine& url_, bool* error, std::string* errorMsg);
 
   std::string url;  // retain copy
   std::string user;  // unescaped
diff --git a/src/main/native/include/support/raw_istream.h b/src/main/native/include/support/raw_istream.h
index 924911ce1c..a79f6b1170 100644
--- a/src/main/native/include/support/raw_istream.h
+++ b/src/main/native/include/support/raw_istream.h
@@ -16,6 +16,7 @@ namespace llvm {
 template <typename T>
 class SmallVectorImpl;
 class StringRef;
+class Twine;
 }
 
 namespace wpi {
@@ -94,7 +95,7 @@ class raw_mem_istream : public raw_istream {
 
 class raw_fd_istream : public raw_istream {
  public:
-  raw_fd_istream(llvm::StringRef filename, std::error_code& ec,
+  raw_fd_istream(const llvm::Twine& filename, std::error_code& ec,
                  std::size_t bufSize = 4096);
   raw_fd_istream(int fd, bool shouldClose, std::size_t bufSize = 4096);
   ~raw_fd_istream() override;