configure.ac:19: installing './compile'
configure.ac:24: installing './config.guess'
configure.ac:24: installing './config.sub'
configure.ac:22: installing './install-sh'
configure.ac:22: installing './missing'
Makefile.am: installing './depcomp'
source_subfolder/examples/opusfile_example.c:155:34: warning: arithmetic on a null pointer treated as a cast from integer to pointer is a GNU extension [-Wnull-pointer-arithmetic]
    of=op_open_url(_argv[1],&ret,OP_GET_SERVER_INFO(&info),NULL);
                                 ^~~~~~~~~~~~~~~~~~~~~~~~~
source_subfolder/include/opusfile.h:844:2: note: expanded from macro 'OP_GET_SERVER_INFO'
 OP_URL_OPT(OP_GET_SERVER_INFO_REQUEST),OP_CHECK_SERVER_INFO_PTR(_info)
 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
source_subfolder/include/opusfile.h:701:41: note: expanded from macro 'OP_URL_OPT'
#define OP_URL_OPT(_request) ((_request)+(char *)0)
                                        ^~~~~~~~~~
1 warning generated.
source_subfolder/examples/seeking_example.c:275:6: warning: arithmetic on a null pointer treated as a cast from integer to pointer is a GNU extension [-Wnull-pointer-arithmetic]
     OP_SSL_SKIP_CERTIFICATE_CHECK(1),NULL);
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
source_subfolder/include/opusfile.h:773:2: note: expanded from macro 'OP_SSL_SKIP_CERTIFICATE_CHECK'
 OP_URL_OPT(OP_SSL_SKIP_CERTIFICATE_CHECK_REQUEST),OP_CHECK_INT(_b)
 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
source_subfolder/include/opusfile.h:701:41: note: expanded from macro 'OP_URL_OPT'
#define OP_URL_OPT(_request) ((_request)+(char *)0)
                                        ^~~~~~~~~~
1 warning generated.
ar: `u' modifier ignored since `D' is the default (see `U')
ar: `u' modifier ignored since `D' is the default (see `U')
CMake Warning:
  Manually-specified variables were not used by the project:

    CMAKE_EXPORT_NO_PACKAGE_REGISTRY