Merge commit '2575b1917b2703fae41a4b4901ad85c888374dfd'

* commit '2575b1917b2703fae41a4b4901ad85c888374dfd':
  build: Add separate flags for checkheaders targets

Merged-by: Clément Bœsch <u@pkh.me>

diff --cc common.mak
Simple merge

diff --cc configure
index b223211,e1f7725..8255d13
--- 1/configure
--- 2/configure
+++ b/configure
@@@ -6141,13 -4850,19 +6141,21 @@@ check_disable_warning -Wno-parenthese
  check_disable_warning -Wno-switch
  check_disable_warning -Wno-format-zero-length
  check_disable_warning -Wno-pointer-sign
 +check_disable_warning -Wno-unused-const-variable
  
+ check_disable_warning_headers(){
+     warning_flag=-W${1#-Wno-}
+     test_cflags $warning_flag && append cflags_headers $1
+ }
+ 
+ check_disable_warning_headers -Wno-deprecated-declarations
+ check_disable_warning_headers -Wno-unused-variable
+ 
  # add some linker flags
  check_ldflags -Wl,--warn-common
 -check_ldflags -Wl,-rpath-link=libswscale:libavfilter:libavdevice:libavformat:libavcodec:libavutil:libavresample
 +check_ldflags -Wl,-rpath-link=libpostproc:libswresample:libswscale:libavfilter:libavdevice:libavformat:libavcodec:libavutil:libavresample
  enabled rpath && add_ldexeflags -Wl,-rpath,$libdir
 +enabled rpath && add_ldlibflags -Wl,-rpath,$libdir
  test_ldflags -Wl,-Bsymbolic && append SHFLAGS -Wl,-Bsymbolic
  
  # add some strip flags
@@@ -6741,7 -5322,8 +6749,8 @@@ HOSTLD_O=$HOSTLD_
  TARGET_EXEC=$target_exec $target_exec_args
  TARGET_PATH=$target_path
  TARGET_SAMPLES=${target_samples:-\$(SAMPLES)}
 -CFLAGS-avplay=$sdl_cflags
 +CFLAGS-ffplay=${sdl2_cflags}
+ CFLAGS_HEADERS=$cflags_headers
  ZLIB=$($ldflags_filter -lz)
  LIB_INSTALL_EXTRA_CMD=$LIB_INSTALL_EXTRA_CMD
  EXTRALIBS=$extralibs