checking for deflate in -lz... yes checking for ID3Tag_Link in -lid3... no
AC_CHECK_LIB adds the "-l" some of the time but does it not in the case of "libz"?
$ autoconf --version autoconf (GNU Autoconf) 2.57
:config.log:
------------
configure:30486: checking for deflate in -lz
configure:30517: gcc -o conftest -ansi -W -Wall -pedantic -Wchar-subscripts -Ws
hadow -Wpointer-arith -Wmissing-prototypes -Wwrite-strings -D_XOPEN_SOURCE=500
-D_BSD_SOURCE -O2 -ansi -W -Wall -pedantic -Wchar-subscripts -Wshadow -Wpointe
r-arith -Wmissing-prototypes -Wwrite-strings -D_XOPEN_SOURCE=500 -D_BSD_SOURCE
-O2 -Wformat-security -Wmissing-format-attribute -Wformat-security -Wmissing-
format-attribute -DQT_THREAD_SUPPORT -D_REENTRANT conftest.c -lz -lvorbisfi
le -lvorbis -lstdc++ >&5
configure:30520: $? = 0
configure:30523: test -s conftest
configure:30526: $? = 0
configure:30538: result: yes
configure:30549: checking for ID3Tag_Link in -lid3
configure:30580: gcc -o conftest -ansi -W -Wall -pedantic -Wchar-subscripts -Ws
hadow -Wpointer-arith -Wmissing-prototypes -Wwrite-strings -D_XOPEN_SOURCE=500
-D_BSD_SOURCE -O2 -ansi -W -Wall -pedantic -Wchar-subscripts -Wshadow -Wpointe
r-arith -Wmissing-prototypes -Wwrite-strings -D_XOPEN_SOURCE=500 -D_BSD_SOURCE
-O2 -Wformat-security -Wmissing-format-attribute -Wformat-security -Wmissing-
format-attribute -DQT_THREAD_SUPPORT -D_REENTRANT conftest.c -lid3 -lvorbis
file -lvorbis -lstdc++ >&5
/usr/lib/gcc-lib/i686-pc-linux-gnu/3.2.3/../../../libid3.so: undefined reference to `uncompress'
/usr/lib/gcc-lib/i686-pc-linux-gnu/3.2.3/../../../libid3.so: undefined reference to `compress'
collect2: ld returned 1 exit status
:snippit of my configure.in: ---------------------------- dnl id3lib library (required) AC_CHECK_LIB( [z], [deflate], configure_enable_id3lib="yes", configure_enable_id3lib="no", )
if test "x$configure_enable_id3lib" = "xyes"; then
AC_CHECK_LIB( id3, ID3Tag_Link,, configure_enable_id3lib="no", )
fi