diff --git a/singleheader/README.md b/singleheader/README.md
old mode 100755
new mode 100644
diff --git a/singleheader/amalgamate_demo.cpp b/singleheader/amalgamate_demo.cpp
index 23395d067..39adffd87 100644
--- a/singleheader/amalgamate_demo.cpp
+++ b/singleheader/amalgamate_demo.cpp
@@ -1,4 +1,4 @@
-/* auto-generated on Thu Apr 23 09:19:14 PDT 2020. Do not edit! */
+/* auto-generated on Thu Apr 23 15:36:58 PDT 2020. Do not edit! */
 
 #include <iostream>
 #include "simdjson.h"
diff --git a/singleheader/simdjson.cpp b/singleheader/simdjson.cpp
index a7d6985fc..17bad5fdc 100644
--- a/singleheader/simdjson.cpp
+++ b/singleheader/simdjson.cpp
@@ -1,4 +1,4 @@
-/* auto-generated on Thu Apr 23 09:19:14 PDT 2020. Do not edit! */
+/* auto-generated on Thu Apr 23 15:36:58 PDT 2020. Do not edit! */
 #include "simdjson.h"
 
 /* used for http://dmalloc.com/ Dmalloc - Debug Malloc Library */
@@ -502,7 +502,7 @@ const detect_best_supported_implementation_on_first_use detect_best_supported_im
 
 internal::atomic_ptr<const implementation> active_implementation{&internal::detect_best_supported_implementation_on_first_use_singleton};
 
-constexpr const std::initializer_list<const implementation *> available_implementation_pointers {
+const std::initializer_list<const implementation *> available_implementation_pointers {
 #if SIMDJSON_IMPLEMENTATION_HASWELL
   &haswell_singleton,
 #endif
diff --git a/singleheader/simdjson.h b/singleheader/simdjson.h
index ffd1a4334..800c8b0de 100644
--- a/singleheader/simdjson.h
+++ b/singleheader/simdjson.h
@@ -1,4 +1,4 @@
-/* auto-generated on Thu Apr 23 09:19:14 PDT 2020. Do not edit! */
+/* auto-generated on Thu Apr 23 15:36:58 PDT 2020. Do not edit! */
 /* begin file simdjson.h */
 #ifndef SIMDJSON_H
 #define SIMDJSON_H
@@ -103,6 +103,20 @@ enum {
 #define IS_ARM64 1
 #endif
 
+#if (!defined(IS_X86_64)) && (!defined(IS_ARM64))
+#if _MSC_VER
+#pragma message("The simdjson library is designed\
+ for 64-bit processors and it seems that you are not\
+compiling for a known 64-bit platform. All fast kernels\
+will be disabled and performance may be poor. Please\
+use a 64-bt target such as x64 or 64-bit ARM.")
+#else
+#error "The simdjson library is designed\
+ for 64-bit processors. It seems that you are not\
+compiling for a known 64-bit platform."
+#endif
+#endif // (!defined(IS_X86_64)) && (!defined(IS_ARM64))
+
 // this is almost standard?
 #undef STRINGIFY_IMPLEMENTATION_
 #undef STRINGIFY
@@ -344,6 +358,7 @@ constexpr size_t DEFAULT_MAX_DEPTH = 1024;
   #define SIMDJSON_PUSH_DISABLE_WARNINGS _Pragma("GCC diagnostic push")
   // gcc doesn't seem to disable all warnings with all and extra, add warnings here as necessary
   #define SIMDJSON_PUSH_DISABLE_ALL_WARNINGS SIMDJSON_PUSH_DISABLE_WARNINGS \
+    SIMDJSON_DISABLE_GCC_WARNING(-Weffc++) \
     SIMDJSON_DISABLE_GCC_WARNING(-Wall) \
     SIMDJSON_DISABLE_GCC_WARNING(-Wconversion) \
     SIMDJSON_DISABLE_GCC_WARNING(-Wextra) \