Merge remote-tracking branch 'qatar/master'

* qatar/master:
  configure: Enable hwaccels without external dependencies by default.
  doc/developer: Clarify symbol naming prefixes section.
Merged-by: Michael Niedermayer <michaelni@gmx.at>

configure

@@ -2199,6 +2199,9 @@ enable safe_bitstream_reader
 enable static
 enable swscale_alpha
 
+# By default, enable only those hwaccels that have no external dependencies.
+enable dxva2 vdpau
+
 # build settings
 SHFLAGS='-shared -Wl,-soname,$$(@F)'
 FFSERVERLDFLAGS=-Wl,-E

doc/developer.texi

@@ -157,13 +157,16 @@ There are the following conventions for naming variables and functions:
 @item
 For local variables no prefix is required.
 @item
-For variables and functions declared as @code{static} no prefix is required.
+For file-scope variables and functions declared as @code{static}, no prefix
+is required.
 @item
-For variables and functions used internally by a library an @code{ff_}
-prefix should be used, e.g. @samp{ff_w64_demuxer}.
+For variables and functions visible outside of file scope, but only used
+internally by a library, an @code{ff_} prefix should be used,
+e.g. @samp{ff_w64_demuxer}.
 @item
-For variables and functions used internally across multiple libraries, use
-@code{avpriv_}. For example, @samp{avpriv_aac_parse_header}.
+For variables and functions visible outside of file scope, used internally
+across multiple libraries, use @code{avpriv_} as prefix, for example,
+@samp{avpriv_aac_parse_header}.
 @item
 Each library has its own prefix for public symbols, in addition to the
 commonly used @code{av_} (@code{avformat_} for libavformat,