dsp.h: bump msvc arm64 version requirement to 16.6
there was a bug in 16.4 causing compile failures with vtbl4_u8():
src\dsp\lossless_neon.c(105): error C2143: syntax error: missing ')'
before '{'
src\dsp\lossless_neon.c(105): error C2168: 'neon_tbl2_q8': too few
actual parameters for intrinsic function
@@ -121,10 +121,11 @@ extern "C" {
// Note: ARM64 is supported in Visual Studio 2017, but requires the direct
// inclusion of arm64_neon.h; Visual Studio 2019 includes this file in
-// arm_neon.h.
+// arm_neon.h. Compile errors were seen with Visual Studio 2019 16.4 with
+// vtbl4_u8(); a fix was made in 16.6.
#if defined(_MSC_VER) && \
((_MSC_VER >= 1700 && defined(_M_ARM)) || \
- (_MSC_VER >= 1920 && defined(_M_ARM64)))
+ (_MSC_VER >= 1926 && defined(_M_ARM64)))
#define WEBP_USE_NEON
#define WEBP_USE_INTRINSICS
#endif
