[PATCH] arm: Don't require a runtime check function for targets with unconditional NEON

If the compiler is set up to unconditionally use NEON instructions
anywhere, we don't need any function for runtime detection.

This fixes building for non-Linux OSes with unconditionally
available NEON, such as iOS and Windows.
---
 pngpriv.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/pngpriv.h b/pngpriv.h
index 2e426cf47..2f033bae8 100644
--- a/pngpriv.h
+++ b/pngpriv.h
@@ -171,6 +171,12 @@
 #              define PNG_ARM_NEON_IMPLEMENTATION 2
 #           endif /* no GNUC support */
 #        endif /* __GNUC__ */
+
+         /* If __ARM_NEON__ or __ARM_NEON is defined, the compiler is free to
+          * use NEON anywhere in generated code, and thus, no runtime check
+          * is needed. */
+#        undef PNG_ARM_NEON_CHECK_SUPPORTED
+
 #     else /* !defined __ARM_NEON__ */
          /* The 'intrinsics' code simply won't compile without this -mfpu=neon:
           */
-- 
2.37.0 (Apple Git-136)