Merge commit '6151e9128ce2a84a443c82b78f5b5cb364ba2ab4'

* commit '6151e9128ce2a84a443c82b78f5b5cb364ba2ab4':
  build: Detect blocks C language extension and add it as VDA dependency

Merged-by: Clément Bœsch <u@pkh.me>

configure

@@ -2004,6 +2004,7 @@ TOOLCHAIN_FEATURES="
     asm_mod_q
     attribute_may_alias
     attribute_packed
+    blocks_extension
     ebp_available
     ebx_available
     gnu_as
@@ -2599,7 +2600,7 @@ d3d11va_deps="d3d11_h dxva_h ID3D11VideoDecoder ID3D11VideoContext"
 dxva2_deps="dxva2api_h DXVA2_ConfigPictureDecode"
 dxva2_extralibs="-luser32"
 dxva2_lib_deps="dxva2"
-vda_framework_deps="VideoDecodeAcceleration_VDADecoder_h"
+vda_framework_deps="VideoDecodeAcceleration_VDADecoder_h blocks_extension"
 vda_framework_extralibs="-framework VideoDecodeAcceleration"
 vda_deps="vda_framework pthreads"
 vda_extralibs="-framework CoreFoundation -framework QuartzCore"
@@ -6176,6 +6177,10 @@ check_disable_warning_headers(){
 check_disable_warning_headers -Wno-deprecated-declarations
 check_disable_warning_headers -Wno-unused-variable
 
+check_cc <<EOF && enable blocks_extension
+void (^block)(void);
+EOF
+
 # add some linker flags
 check_ldflags -Wl,--warn-common
 check_ldflags -Wl,-rpath-link=libpostproc:libswresample:libswscale:libavfilter:libavdevice:libavformat:libavcodec:libavutil:libavresample