diff --git a/StdLib/LibC/String/Copying.c b/StdLib/LibC/String/Copying.c
index 18498d6f87..e27519e24c 100644
--- a/StdLib/LibC/String/Copying.c
+++ b/StdLib/LibC/String/Copying.c
@@ -19,11 +19,12 @@
 #include  <stdlib.h>
 #include  <string.h>
 
-/** Do not define memcpy for IPF+GCC builds.
+/** Do not define memcpy for IPF+GCC or ARM+GCC builds.
     For IPF, using a GCC compiler, the memcpy function is converted to
     CopyMem by objcpy during build.
+    For ARM, the memcpy function is provided by the CompilerIntrinsics library.
 **/
-#if  !(defined(MDE_CPU_IPF) && defined(__GNUC__))
+#if !((defined(MDE_CPU_IPF) || defined(MDE_CPU_ARM)) && defined(__GNUC__))
 /** The memcpy function copies n characters from the object pointed to by s2
     into the object pointed to by s1.
 
diff --git a/StdLib/LibC/gdtoa/gdtoa.inf b/StdLib/LibC/gdtoa/gdtoa.inf
index fbe3ac1b63..48b7df403f 100644
--- a/StdLib/LibC/gdtoa/gdtoa.inf
+++ b/StdLib/LibC/gdtoa/gdtoa.inf
@@ -44,6 +44,7 @@
 
 [Sources.ARM]
   strtof.c
+  Ipf/strtold.c
 
 [Sources]
   strtod.c      # Public interfaces
diff --git a/StdLibPrivateInternalFiles/DoNotUse.dec b/StdLibPrivateInternalFiles/DoNotUse.dec
index 1b9bdbdbe4..da6061b720 100644
--- a/StdLibPrivateInternalFiles/DoNotUse.dec
+++ b/StdLibPrivateInternalFiles/DoNotUse.dec
@@ -33,3 +33,7 @@
 
 [Includes.ARM]
   Include/Arm
+
+[Includes.AARCH64]
+  # Use the ARM headers for now.
+  Include/Arm