build: Properly unset CPPFLAGS, LDFLAGS, LIBS.

Currently the directories specified via --with-ogg-headers and
--with-ogg-libs are taken into account also for vorbis/speex/opus
detection. This patch makes sure we start with a pristine values
for the three variables.

diff --git a/configure.ac b/configure.ac
index 16927c58e2aed1ec5e8f8a4d8ce32170312fdab8..f0749cc69424db44977a3ba13dea400fad31b27c 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -380,11 +380,17 @@ if test -n "$with_ogg_libs"; then
 fi
 AC_CHECK_HEADERS([ogg/ogg.h], [], [ have_ogg="no"; ])
 AC_CHECK_LIB([ogg], [ogg_stream_init], [], [ have_ogg="no" ])
+CPPFLAGS="$OLD_CPPFLAGS"
+LDFLAGS="$OLD_LDFLAGS"
+LIBS="$OLD_LIBS"
 
 have_vorbis="yes"
 have_speex="yes"
 have_opus="yes"
 if test "$have_ogg" = "yes"; then
+       OLD_CPPFLAGS="$CPPFLAGS"
+       OLD_LDFLAGS="$LDFLAGS"
+       OLD_LIBS="$LIBS"
        # vorbis
        if test -n "$with_vorbis_headers"; then
                vorbis_cppflags="-I$with_vorbis_headers"
@@ -396,8 +402,14 @@ if test "$have_ogg" = "yes"; then
        fi
        AC_CHECK_HEADERS([vorbis/codec.h], [], [ have_vorbis="no" ])
        AC_CHECK_LIB([vorbis], [vorbis_info_init], [], [ have_vorbis="no" ])
+       CPPFLAGS="$OLD_CPPFLAGS"
+       LDFLAGS="$OLD_LDFLAGS"
+       LIBS="$OLD_LIBS"
 
        # speex
+       OLD_CPPFLAGS="$CPPFLAGS"
+       OLD_LDFLAGS="$LDFLAGS"
+       OLD_LIBS="$LIBS"
        if test -n "$with_speex_headers"; then
                speex_cppflags="-I$with_speex_headers"
                CPPFLAGS="$CPPFLAGS $speex_cppflags"
@@ -408,8 +420,14 @@ if test "$have_ogg" = "yes"; then
        fi
        AC_CHECK_LIB([speex], [speex_decoder_init], [], [ have_speex="no" ])
        AC_CHECK_HEADERS([speex/speex.h], [], [ have_speex="no" ])
+       CPPFLAGS="$OLD_CPPFLAGS"
+       LDFLAGS="$OLD_LDFLAGS"
+       LIBS="$OLD_LIBS"
 
        # opus
+       OLD_CPPFLAGS="$CPPFLAGS"
+       OLD_LDFLAGS="$LDFLAGS"
+       OLD_LIBS="$LIBS"
        if test -n "$with_opus_headers"; then
                opus_cppflags="-I$with_opus_headers"
                CPPFLAGS="$CPPFLAGS $opus_cppflags"
@@ -420,6 +438,9 @@ if test "$have_ogg" = "yes"; then
        fi
        AC_CHECK_LIB([opus], [opus_multistream_decode], [], [ have_opus="no" ])
        AC_CHECK_HEADERS([opus/opus.h], [], [ have_opus="no" ])
+       CPPFLAGS="$OLD_CPPFLAGS"
+       LDFLAGS="$OLD_LDFLAGS"
+       LIBS="$OLD_LIBS"
 else
        AC_MSG_WARN([vorbis/speex/opus depend on libogg, which was not detected])
        have_vorbis="no"
@@ -461,9 +482,6 @@ if test "$have_opus" = "yes"; then
 else
        AC_MSG_WARN([no ogg/opus $msg])
 fi
-CPPFLAGS="$OLD_CPPFLAGS"
-LDFLAGS="$OLD_LDFLAGS"
-LIBS="$OLD_LIBS"
 ########################################################################### faad
 have_faad=yes
 OLD_CPPFLAGS="$CPPFLAGS"