Examples fail on mac

[AlanFoster]

I'm attempting to run the examples:

cd libuv
./autogen.sh
./configure
make

Full output

➜  libuv git:(master) ./configure 
checking for a BSD-compatible install... /usr/local/bin/ginstall -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /usr/local/bin/gmkdir -p
checking for gawk... no
checking for mawk... no
checking for nawk... no
checking for awk... awk
checking whether make sets $(MAKE)... yes
checking whether make supports nested variables... yes
checking build system type... x86_64-apple-darwin18.7.0
checking host system type... x86_64-apple-darwin18.7.0
checking for gcc... gcc
checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables... 
checking whether we are cross compiling... no
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ISO C89... none needed
checking whether gcc understands -c and -o together... yes
checking whether make supports the include directive... yes (GNU style)
checking dependency style of gcc... gcc3
checking if gcc supports -fvisibility=hidden flag... yes
checking if gcc supports -g flag... yes
checking if gcc supports -std=gnu89 flag... yes
checking if gcc supports -pedantic flag... yes
checking if gcc supports -Wall flag... yes
checking if gcc supports -Wextra flag... yes
checking if gcc supports -Wno-unused-parameter flag... yes
checking for ar... ar
checking the archiver (ar) interface... ar
checking how to print strings... printf
checking for a sed that does not truncate output... /usr/bin/sed
checking for grep that handles long lines and -e... /usr/bin/grep
checking for egrep... /usr/bin/grep -E
checking for fgrep... /usr/bin/grep -F
checking for ld used by gcc... /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld
checking if the linker (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld) is GNU ld... no
checking for BSD- or MS-compatible name lister (nm)... /usr/local/opt/binutils/bin/nm -B
checking the name lister (/usr/local/opt/binutils/bin/nm -B) interface... BSD nm
checking whether ln -s works... yes
checking the maximum length of command line arguments... 196608
checking how to convert x86_64-apple-darwin18.7.0 file names to x86_64-apple-darwin18.7.0 format... func_convert_file_noop
checking how to convert x86_64-apple-darwin18.7.0 file names to toolchain format... func_convert_file_noop
checking for /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld option to reload object files... -r
checking for objdump... objdump
checking how to recognize dependent libraries... pass_all
checking for dlltool... dlltool
checking how to associate runtime and link libraries... printf %s\n
checking for archiver @FILE support... @
checking for strip... strip
checking for ranlib... ranlib
checking command to parse /usr/local/opt/binutils/bin/nm -B output from gcc object... failed
checking for sysroot... no
checking for a working dd... /bin/dd
checking how to truncate binary pipes... /bin/dd bs=4096 count=1
checking for mt... no
checking if : is a manifest tool... no
checking for dsymutil... dsymutil
checking for nmedit... nmedit
checking for lipo... lipo
checking for otool... otool
checking for otool64... no
checking for -single_module linker flag... yes
checking for -exported_symbols_list linker flag... yes
checking for -force_load linker flag... no
checking how to run the C preprocessor... gcc -E
checking for ANSI C header files... yes
checking for sys/types.h... yes
checking for sys/stat.h... yes
checking for stdlib.h... yes
checking for string.h... yes
checking for memory.h... yes
checking for strings.h... yes
checking for inttypes.h... yes
checking for stdint.h... yes
checking for unistd.h... yes
checking for dlfcn.h... yes
checking for objdir... .libs
checking if gcc supports -fno-rtti -fno-exceptions... yes
checking for gcc option to produce PIC... -fno-common -DPIC
checking if gcc PIC flag -fno-common -DPIC works... yes
checking if gcc static flag -static works... no
checking if gcc supports -c -o file.o... yes
checking if gcc supports -c -o file.o... (cached) yes
checking whether the gcc linker (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld) supports shared libraries... yes
checking dynamic linker characteristics... darwin18.7.0 dyld
checking how to hardcode library paths into programs... immediate
checking whether stripping libraries is possible... yes
checking if libtool supports shared libraries... yes
checking whether to build shared libraries... yes
checking whether to build static libraries... yes
checking whether make supports nested variables... (cached) yes
checking for dlopen in -ldl... yes
checking for kstat_lookup in -lkstat... no
checking for kvm_open in -lkvm... no
checking for gethostbyname in -lnsl... no
checking for perfstat_cpu in -lperfstat... no
checking for pthread_mutex_init in -lpthread... yes
checking for clock_gettime in -lrt... no
checking for sendfile in -lsendfile... no
checking for socket in -lsocket... no
checking for special C compiler options needed for large files... no
checking for _FILE_OFFSET_BITS value needed for large files... no
checking for pkg-config... yes
checking that generated files are newer than configure... done
configure: creating ./config.status
config.status: creating libuv.pc
config.status: creating Makefile
config.status: executing depfiles commands
config.status: executing libtool commands
➜  libuv git:(master) make
  CC       src/libuv_la-fs-poll.lo
  CC       src/libuv_la-inet.lo
  CC       src/libuv_la-threadpool.lo
  CC       src/libuv_la-uv-common.lo
  CC       src/libuv_la-version.lo
  CC       src/unix/libuv_la-async.lo
  CC       src/unix/libuv_la-core.lo
  CC       src/unix/libuv_la-dl.lo
  CC       src/unix/libuv_la-fs.lo
  CC       src/unix/libuv_la-getaddrinfo.lo
  CC       src/unix/libuv_la-getnameinfo.lo
  CC       src/unix/libuv_la-loop-watcher.lo
  CC       src/unix/libuv_la-loop.lo
  CC       src/unix/libuv_la-pipe.lo
  CC       src/unix/libuv_la-poll.lo
  CC       src/unix/libuv_la-process.lo
  CC       src/unix/libuv_la-signal.lo
  CC       src/unix/libuv_la-stream.lo
src/unix/stream.c:1054:19: warning: variable length array folded to constant array as
      an extension [-Wgnu-folding-constant]
  char cmsg_space[CMSG_SPACE(UV__CMSG_FD_SIZE)];
                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/socket.h:647:33: note: 
      expanded from macro 'CMSG_SPACE'
  ...(__DARWIN_ALIGN32(sizeof(struct cmsghdr)) + __DARWIN_ALIGN32(l))
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/unix/stream.c:1054:19: note: cast that performs the conversions of a
      reinterpret_cast is not allowed in a constant expression
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/socket.h:647:34: note: 
      expanded from macro 'CMSG_SPACE'
#define CMSG_SPACE(l)           (__DARWIN_ALIGN32(sizeof(struct cmsghdr)) + _...
                                 ^
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/i386/_param.h:43:42: note: 
      expanded from macro '__DARWIN_ALIGN32'
#define       __DARWIN_ALIGN32(p)       ((__darwin_size_t)((char *)(__darwin_...
                                         ^
1 warning generated.
  CC       src/unix/libuv_la-tcp.lo
  CC       src/unix/libuv_la-thread.lo
  CC       src/unix/libuv_la-timer.lo
  CC       src/unix/libuv_la-tty.lo
  CC       src/unix/libuv_la-udp.lo
  CC       src/unix/libuv_la-darwin.lo
  CC       src/unix/libuv_la-darwin-proctitle.lo
  CC       src/unix/libuv_la-fsevents.lo
  CC       src/unix/libuv_la-kqueue.lo
  CC       src/unix/libuv_la-proctitle.lo
  CCLD     libuv.la
ar: `u' modifier ignored since `D' is the default (see `U')

Followed by:

To build the examples run make in the code/ directory.

Which gives me the following error on osx:

➜  code git:(master) make
gcc -g -Wall -I/Users/user/Documents/code/uvbook/code/../libuv/include -framework CoreServices  -o plugin/plugin plugin/main.c /Users/user/Documents/code/uvbook/code/../libuv/.libs/libuv.a 
ld: warning: ignoring file /Users/user/Documents/code/uvbook/code/../libuv/.libs/libuv.a, building for macOS-x86_64 but attempting to link with file built for unknown-unsupported file format ( 0x21 0x3C 0x61 0x72 0x63 0x68 0x3E 0x0A 0x2F 0x20 0x20 0x20 0x20 0x20 0x20 0x20 )
Undefined symbols for architecture x86_64:
  "_uv_dlerror", referenced from:
      _main in main-7454f5.o
  "_uv_dlopen", referenced from:
      _main in main-7454f5.o
  "_uv_dlsym", referenced from:
      _main in main-7454f5.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [plugin/plugin] Error 1

clang version:

clang -v  
Apple clang version 11.0.0 (clang-1100.0.33.16)
Target: x86_64-apple-darwin18.7.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin

OS:

macOS Mojave
10.14.6 (18G3020)

Any help would be appreciated 👍

[AlanFoster]

I'm running in a docker container now:

docker run -it --rm -v $(pwd):$(pwd) -w $(pwd) gcc:10.2.0 /bin

Running through the same steps as above works for me now.

Working output

# ./autogen.sh 
+ libtoolize
libtoolize: putting auxiliary files in '.'.
libtoolize: linking file './ltmain.sh'
libtoolize: putting macros in AC_CONFIG_MACRO_DIRS, 'm4'.
libtoolize: linking file 'm4/libtool.m4'
libtoolize: linking file 'm4/ltoptions.m4'
libtoolize: linking file 'm4/ltsugar.m4'
libtoolize: linking file 'm4/ltversion.m4'
libtoolize: linking file 'm4/lt~obsolete.m4'
+ aclocal -I m4
+ autoconf
+ automake --add-missing --copy
# ./configure
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... no
checking for mawk... mawk
checking whether make sets $(MAKE)... yes
checking whether make supports nested variables... yes
checking build system type... x86_64-pc-linux-gnu
checking host system type... x86_64-pc-linux-gnu
checking for gcc... gcc
checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables... 
checking whether we are cross compiling... no
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ISO C89... none needed
checking whether gcc understands -c and -o together... yes
checking whether make supports the include directive... yes (GNU style)
checking dependency style of gcc... gcc3
checking if gcc supports -fvisibility=hidden flag... yes
checking if gcc supports -g flag... yes
checking if gcc supports -std=gnu89 flag... yes
checking if gcc supports -pedantic flag... yes
checking if gcc supports -Wall flag... yes
checking if gcc supports -Wextra flag... yes
checking if gcc supports -Wno-unused-parameter flag... yes
checking for ar... ar
checking the archiver (ar) interface... ar
checking how to print strings... printf
checking for a sed that does not truncate output... /bin/sed
checking for grep that handles long lines and -e... /bin/grep
checking for egrep... /bin/grep -E
checking for fgrep... /bin/grep -F
checking for ld used by gcc... /usr/bin/ld
checking if the linker (/usr/bin/ld) is GNU ld... yes
checking for BSD- or MS-compatible name lister (nm)... /usr/bin/nm -B
checking the name lister (/usr/bin/nm -B) interface... BSD nm
checking whether ln -s works... yes
checking the maximum length of command line arguments... 1572864
checking how to convert x86_64-pc-linux-gnu file names to x86_64-pc-linux-gnu format... func_convert_file_noop
checking how to convert x86_64-pc-linux-gnu file names to toolchain format... func_convert_file_noop
checking for /usr/bin/ld option to reload object files... -r
checking for objdump... objdump
checking how to recognize dependent libraries... pass_all
checking for dlltool... no
checking how to associate runtime and link libraries... printf %s\n
checking for archiver @FILE support... @
checking for strip... strip
checking for ranlib... ranlib
checking command to parse /usr/bin/nm -B output from gcc object... ok
checking for sysroot... no
checking for a working dd... /bin/dd
checking how to truncate binary pipes... /bin/dd bs=4096 count=1
checking for mt... no
checking if : is a manifest tool... no
checking how to run the C preprocessor... gcc -E
checking for ANSI C header files... yes
checking for sys/types.h... yes
checking for sys/stat.h... yes
checking for stdlib.h... yes
checking for string.h... yes
checking for memory.h... yes
checking for strings.h... yes
checking for inttypes.h... yes
checking for stdint.h... yes
checking for unistd.h... yes
checking for dlfcn.h... yes
checking for objdir... .libs
checking if gcc supports -fno-rtti -fno-exceptions... no
checking for gcc option to produce PIC... -fPIC -DPIC
checking if gcc PIC flag -fPIC -DPIC works... yes
checking if gcc static flag -static works... yes
checking if gcc supports -c -o file.o... yes
checking if gcc supports -c -o file.o... (cached) yes
checking whether the gcc linker (/usr/bin/ld -m elf_x86_64) supports shared libraries... yes
checking whether -lc should be explicitly linked in... no
checking dynamic linker characteristics... GNU/Linux ld.so
checking how to hardcode library paths into programs... immediate
checking whether stripping libraries is possible... yes
checking if libtool supports shared libraries... yes
checking whether to build shared libraries... yes
checking whether to build static libraries... yes
checking whether make supports nested variables... (cached) yes
checking for dlopen in -ldl... yes
checking for kstat_lookup in -lkstat... no
checking for kvm_open in -lkvm... no
checking for gethostbyname in -lnsl... yes
checking for perfstat_cpu in -lperfstat... no
checking for pthread_mutex_init in -lpthread... yes
checking for clock_gettime in -lrt... yes
checking for sendfile in -lsendfile... no
checking for socket in -lsocket... no
checking for special C compiler options needed for large files... no
checking for _FILE_OFFSET_BITS value needed for large files... no
checking for pkg-config... yes
checking that generated files are newer than configure... done
configure: creating ./config.status
makconfig.status: creating libuv.pc
config.status: creating Makefile
econfig.status: executing depfiles commands
config.status: executing libtool commands
# make
  CC       src/libuv_la-fs-poll.lo
  CC       src/libuv_la-inet.lo
  CC       src/libuv_la-threadpool.lo
  CC       src/libuv_la-uv-common.lo
  CC       src/libuv_la-version.lo
  CC       src/unix/libuv_la-async.lo
  CC       src/unix/libuv_la-core.lo
  CC       src/unix/libuv_la-dl.lo
  CC       src/unix/libuv_la-fs.lo
  CC       src/unix/libuv_la-getaddrinfo.lo
  CC       src/unix/libuv_la-getnameinfo.lo
  CC       src/unix/libuv_la-loop-watcher.lo
  CC       src/unix/libuv_la-loop.lo
  CC       src/unix/libuv_la-pipe.lo
  CC       src/unix/libuv_la-poll.lo
  CC       src/unix/libuv_la-process.lo
  CC       src/unix/libuv_la-signal.lo
  CC       src/unix/libuv_la-stream.lo
  CC       src/unix/libuv_la-tcp.lo
  CC       src/unix/libuv_la-thread.lo
  CC       src/unix/libuv_la-timer.lo
  CC       src/unix/libuv_la-tty.lo
  CC       src/unix/libuv_la-udp.lo
  CC       src/unix/libuv_la-linux-core.lo
src/unix/linux-core.c: In function 'uv__io_poll':
src/unix/linux-core.c:268:5: warning: converting a packed 'struct uv__epoll_event' pointer (alignment 1) to a 'uv__io_t' {aka 'struct uv__io_s'} pointer (alignment 8) may result in an unaligned pointer value [-Waddress-of-packed-member]
  268 |     loop->watchers[loop->nwatchers] = (void*) events;
      |     ^~~~
In file included from src/unix/internal.h:37,
                 from src/unix/linux-core.c:22:
src/unix/linux-syscalls.h:97:8: note: defined here
   97 | struct uv__epoll_event {
      |        ^~~~~~~~~~~~~~~
In file included from ./include/uv.h:61,
                 from src/unix/linux-core.c:21:
./include/uv-unix.h:84:8: note: defined here
   84 | struct uv__io_s {
      |        ^~~~~~~~
  CC       src/unix/libuv_la-linux-inotify.lo
  CC       src/unix/libuv_la-linux-syscalls.lo
  CC       src/unix/libuv_la-proctitle.lo
  CCLD     libuv.la
ar: `u' modifier ignored since `D' is the default (see `U')

# ./helloworld/helloworld 
Now quitting.

[nikhilm]

Umm... it is quite possible that on macOS, the libuv.la file is produced at the top-level instead of the .libs/ directory. I only had access to a Linux machine back when I wrote this. You could try changing the path in the code Makefile

uvbook/code/Makefile

Line 30 in 99fc7fd

UV_LIB=$(UV_PATH)/.libs/libuv.a

Just so you are aware, this book was long ago merged into the libuv official docs and it is possible they have up to date and working code and examples.