Merge remote-tracking branch 'cigaes/master'

* cigaes/master:
  configure: add a note about pkg-config --static.
  configure: add optional pkg-config helper and use it.
Merged-by: Michael Niedermayer <michaelni@gmx.at>

configure

@@ -1203,13 +1203,17 @@ require_cpp(){
     check_lib_cpp "$headers" "$classes" "$@" || die "ERROR: $name not found"
 }
 
-require_pkg_config(){
+use_pkg_config(){
     pkg="$1"
-    check_pkg_config "$@" || die "ERROR: $pkg not found"
+    check_pkg_config "$@" || return 1
     add_cflags    $(get_safe ${pkg}_cflags)
     add_extralibs $(get_safe ${pkg}_libs)
 }
 
+require_pkg_config(){
+    use_pkg_config "$@" || die "ERROR: $pkg not found using pkg-config$pkg_config_fail_message"
+}
+
 require_libfreetype(){
     log require_libfreetype "$@"
     pkg="freetype2"
@@ -3066,9 +3070,13 @@ set_default arch cc cxx doxygen pkg_config ranlib strip sysinclude \
 enabled cross_compile || host_cc_default=$cc
 set_default host_cc
 
+pkg_config_fail_message=""
 if ! $pkg_config --version >/dev/null 2>&1; then
     warn "$pkg_config not found, library detection may fail."
     pkg_config=false
+elif is_in -static $cc $LDFLAGS && ! is_in --static $pkg_config $pkg_config_flags; then
+    pkg_config_fail_message="
+Note: When building a static binary, add --pkg-config-flags=\"--static\"."
 fi
 
 if test $doxygen != $doxygen_default && \
@@ -4875,9 +4883,8 @@ enabled libquvi           && require_pkg_config libquvi quvi/quvi.h quvi_init
 enabled librtmp           && require_pkg_config librtmp librtmp/rtmp.h RTMP_Socket
 enabled libschroedinger   && require_pkg_config schroedinger-1.0 schroedinger/schro.h schro_init
 enabled libshine          && require_pkg_config shine shine/layer3.h shine_encode_buffer
-enabled libsmbclient      && { { check_pkg_config smbclient libsmbclient.h smbc_init &&
-                                 require_pkg_config smbclient libsmbclient.h smbc_init; } ||
-                                 require smbclient libsmbclient.h smbc_init -lsmbclient; }
+enabled libsmbclient      && { check_pkg_config smbclient libsmbclient.h smbc_init ||
+                               require smbclient libsmbclient.h smbc_init -lsmbclient; }
 enabled libsoxr           && require libsoxr soxr.h soxr_create -lsoxr
 enabled libssh            && require_pkg_config libssh libssh/sftp.h sftp_init
 enabled libspeex          && require_pkg_config speex speex/speex.h speex_decoder_init -lspeex
@@ -4903,8 +4910,7 @@ enabled libvpx            && {
     enabled libvpx_vp9_encoder && { check_lib2 "vpx/vpx_encoder.h vpx/vp8cx.h" "vpx_codec_vp9_cx VP9E_SET_AQ_MODE" -lvpx || disable libvpx_vp9_encoder; } }
 enabled libwavpack        && require libwavpack wavpack/wavpack.h WavpackOpenFileOutput  -lwavpack
 enabled libwebp           && require_pkg_config "libwebp >= 0.2.0" webp/encode.h WebPGetEncoderVersion
-enabled libx264           && { { check_pkg_config x264 "stdint.h x264.h" x264_encoder_encode &&
-                                 require_pkg_config x264 "stdint.h x264.h" x264_encoder_encode; } ||
+enabled libx264           && { use_pkg_config x264 "stdint.h x264.h" x264_encoder_encode ||
                                { require libx264 x264.h x264_encoder_encode -lx264 &&
                                  warn "using libx264 without pkg-config"; } } &&
                              { check_cpp_condition x264.h "X264_BUILD >= 118" ||