Handle UBSan warnings about unaligned storing and reading

Fixes UBSan issues found in
	  8 - test_basic_parse (Failed)
	  9 - test_json_parser (Failed)
	 10 - test_json_printer (Failed)
	 11 - test_json (Failed)
	 12 - json_test_uql (Failed)
	 13 - json_test_uql_off (Failed)
	 14 - json_test_uq (Failed)
	 15 - json_test_uq_off (Failed)
	 16 - json_test (Failed)
	 19 - optional_scalars_test (Failed)

Signed-off-by: Björn Svensson <[email protected]>

Author: bjosv

include/flatcc/portable/pprintint.h

@@ -102,7 +102,9 @@ static int print_int(int n, char *p);
 static int print_long(long n, char *p);
 
 
-#if defined(__i386__) || defined(__x86_64__) || defined(_M_IX86) || defined(_M_X64)
+/* The UBSan will warn about storing to misaligned address. */
+#if !(defined(__has_feature) && __has_feature(undefined_behavior_sanitizer)) && \
+    (defined(__i386__) || defined(__x86_64__) || defined(_M_IX86) || defined(_M_X64))
 #define __print_unaligned_copy_16(p, q) (*(uint16_t*)(p) = *(uint16_t*)(q))
 #else
 #define __print_unaligned_copy_16(p, q)                                     \

include/flatcc/portable/punaligned.h

@@ -28,7 +28,10 @@ extern "C" {
 
 #ifndef PORTABLE_UNALIGNED_ACCESS
 
-#if defined(__i386__) || defined(__x86_64__) || defined(_M_IX86) || defined(_M_X64)
+#if defined(__has_feature) && __has_feature(undefined_behavior_sanitizer)
+/* The UBSan will warn about unaligned access. */
+#define PORTABLE_UNALIGNED_ACCESS 0
+#elif defined(__i386__) || defined(__x86_64__) || defined(_M_IX86) || defined(_M_X64)
 #define PORTABLE_UNALIGNED_ACCESS 1
 #else
 #define PORTABLE_UNALIGNED_ACCESS 0