Fix compile errors for ARM targets when libyuv_use_neon = false

When building for ARM target with "libyuv_use_neon" set to false, the
build fails because there are still codes that reference to the NEON
related functions. To disable these code parts completely, the
LIBYUV_DISABLE_NEON macro should be defined when the "libyuv_use_neon"
is set to false.

Bug: libyuv:929
Change-Id: I8f34288d0d17dd29b85db004e62d83e4ace3d595
Reviewed-on: https://chromium-review.googlesource.com/c/libyuv/libyuv/+/3628112
Reviewed-by: Mirko Bonadei <mbonadei@chromium.org>
Commit-Queue: Mirko Bonadei <mbonadei@chromium.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/BUILD.gn b/BUILD.gn
index 2c9c3e6e..a72ff065 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -27,6 +27,10 @@ config("libyuv_config") {
   if (is_android && current_cpu != "arm64") {
     ldflags = [ "-Wl,--dynamic-linker,/system/bin/linker" ]
   }
+
+  if (!libyuv_use_neon) {
+    defines = [ "LIBYUV_DISABLE_NEON" ]
+  }
 }
 
 # This target is built when no specific target is specified on the command line.