[Scons-users] InstallVersionedLibrary sometimes fails when symlinking

[Andrew C. Morrow]

Hi Bill -

Were you able to repro this? If so, should I file a ticket?

Also, is there some documentation on the SCons bugfix and release cycle?
I've noticed that there are only infrequently 'z +1' releases of SCons
x.y.z. If the problem with InstallVersionedLibrary is legitimate, should I
expect to see a fix in a to-be-released-somewhat-soonish SCons 2.3.1 bugfix
release, or longer term in some future SCons 2.4 release?

Thanks,
Andrew



On Fri, May 24, 2013 at 4:36 PM, Andrew C. Morrow <andrew.c.morrow at gmail.com

> wrote:



>

> Well, the complete example I posted above was on OS X Mountain Lion. But

> I'm experiencing the same problem on Linux. My first email with the strace

> output was from Ubuntu 13.04.

>

>

> On Fri, May 24, 2013 at 4:04 PM, Bill Deegan <bill at baddogconsulting.com>wrote:

>

>> What platform are you on?

>>

>> -Bill

>>

>>

>> On Fri, May 24, 2013 at 7:16 AM, Andrew C. Morrow <

>> andrew.c.morrow at gmail.com> wrote:

>>

>>>

>>> Here is a complete example demonstrating the problem

>>>

>>> SConstruct:

>>>

>>> EnsureSConsVersion(2, 3, 0)

>>>

>>> AddOption('--prefix',

>>>           dest='prefix',

>>>           type='string',

>>>           nargs=1,

>>>           action='store',

>>>           metavar='DIR',

>>>           help='installation prefix')

>>>

>>> env = Environment(

>>>     tools = ["default"],

>>>     PREFIX = GetOption('prefix'))

>>>

>>> env.SConscript('src/SConscript', variant_dir='build', exports=['env'])

>>>

>>>

>>>

>>> src/SConscript:

>>>

>>> Import('env')

>>>

>>> sources = [

>>>     'foo.cpp',

>>> ]

>>>

>>> headers = [

>>>     'foo.hpp'

>>> ]

>>>

>>> sharedLibEnv = env.Clone(SHLIBVERSION='0.1.2')

>>> sharedLib = sharedLibEnv.SharedLibrary(

>>>     target='foo',

>>>     source=sources,

>>> )

>>>

>>> sharedLibEnv.InstallVersionedLib("$PREFIX/lib", sharedLib)

>>> sharedLibEnv.Install("$PREFIX/include", headers)

>>>

>>>

>>> src/foo.hpp:

>>>

>>> #include <iosfwd>

>>>

>>> namespace foo {

>>>

>>>     void say_hello(std::ostream& stream);

>>>

>>> } // namespace foo

>>>

>>>

>>> src/foo.cpp:

>>>

>>> #include "foo.hpp"

>>>

>>> #include <ostream>

>>>

>>> namespace foo {

>>>

>>>     void say_hello(std::ostream& stream) {

>>>         stream << "Hello, World!\n";

>>>     }

>>>

>>> } // namespace foo

>>>

>>>

>>>

>>> OK, so now build the 'install' target, specifying some prefix:

>>>

>>> scons --prefix=$(pwd)/install install

>>> scons: Reading SConscript files ...

>>> scons: done reading SConscript files.

>>> scons: Building targets ...

>>> Install file: "build/foo.hpp" as "install/include/foo.hpp"

>>> g++ -o build/foo.os -c -fPIC build/foo.cpp

>>> g++ -o build/libfoo.0.1.2.dylib -dynamiclib -current_version 0.1.2

>>> -compatibility_version 0.1.2 -undefined dynamic_lookup build/foo.os

>>> Install file: "build/libfoo.0.1.2.dylib" as

>>> "install/lib/libfoo.0.1.2.dylib"

>>> scons: done building targets.

>>>

>>> Now, make a trivial change to foo.cpp to force a relink (like change the

>>> string), and rebuild:

>>>

>>> scons --prefix=$(pwd)/install install

>>> scons: Reading SConscript files ...

>>> scons: done reading SConscript files.

>>> scons: Building targets ...

>>> g++ -o build/foo.os -c -fPIC build/foo.cpp

>>> g++ -o build/libfoo.0.1.2.dylib -dynamiclib -current_version 0.1.2

>>> -compatibility_version 0.1.2 -undefined dynamic_lookup build/foo.os

>>> Install file: "build/libfoo.0.1.2.dylib" as

>>> "install/lib/libfoo.0.1.2.dylib"

>>> scons: *** [install/lib/libfoo.0.1.2.dylib] File exists

>>> scons: building terminated because of errors.

>>>

>>> The build fails while trying to symlink.

>>>

>>> Thanks,

>>> Andrew

>>>

>>>

>>>

>>> On Thu, May 23, 2013 at 1:30 PM, Andrew C. Morrow <

>>> andrew.c.morrow at gmail.com> wrote:

>>>

>>>>

>>>> Hi -

>>>>

>>>> I've recently been experimenting with the new versioned shared library

>>>> support in SCons 2.3.0, which so far looks really nice, so thanks for that.

>>>>

>>>> I have, I think, found one issue, which is that it appears that if you

>>>>

>>>> - have used InstallVersionedLibrary and produced a target and symlink

>>>> chain in your install directory

>>>> - update a dependency such that the library is rebuilt

>>>> - reinstall

>>>>

>>>> The build fails while attempting to write the symlinks. For my build

>>>> this looks like:

>>>>

>>>> scons: done reading SConscript files.

>>>> scons: Building targets ...

>>>> Install file: "client_build/libfoo.so.2.3.4" as

>>>> "/dev/opt/lib/libfoo.so.2.3.4"

>>>> scons: *** [/dev/opt/lib/libfoo.so.2.3.4] File exists

>>>>

>>>> Running under strace, it is clear that the attempt to create the

>>>> symlink is failing because it already exists in the install directory.

>>>>

>>>> pid 22278] stat("client_build/libfoo.so.2.3.4", {st_mode=S_IFREG|0755,

>>>> st_size=20255704, ...}) = 0

>>>> [pid 22278] utimes("/dev/opt/lib/libfoo.so.2.3.4", {{1369328366, 0},

>>>> {1369328365, 0}}) = 0

>>>> [pid 22278] chmod("/dev/opt/lib/libfoo.so.2.3.4", 0755) = 0

>>>> [pid 22278] stat("client_build/libfoo.so.2.3.4", {st_mode=S_IFREG|0755,

>>>> st_size=20255704, ...}) = 0

>>>> [pid 22278] chmod("/dev/opt/lib/libfoo.so.2.3.4", 0755) = 0

>>>> [pid 22278] symlink("libfoo.so.2.3.4", "/dev/opt/lib/libfoo.so") = -1

>>>> EEXIST (File exists)

>>>>

>>>> I think the same thing can occur in the build directory as well. If I

>>>> remove client_build/libfoo.so.2.3.4 and rebuild, I get a similar error and

>>>> strace:

>>>>

>>>> scons: Building targets ...

>>>> generate_buildinfo(["build/buildinfo.cpp"], ['\n#include

>>>> <string>\n#include <boost/version.hpp>\n\n#include

>>>> "mongo/util/version.h"\n\nnamespace mongo {\n    const char * gitVersion()

>>>> { return "%(git_version)s"; }\n    const char * compiledJSEngine() { return

>>>> "%(js_engine)s"; }\n    const char * allocator() { return "%(allocator)s";

>>>> }\n    const char * loaderFlags() { return "%(loader_flags)s"; }\n    const

>>>> char * compilerFlags() { return "%(compiler_flags)s"; }\n    std::string

>>>> sysInfo() { return "%(sys_info)s BOOST_LIB_VERSION=" BOOST_LIB_VERSION ;

>>>> }\n}  // namespace mongo\n'])

>>>> g++ <library-rebuild>

>>>> scons: *** [client_build/libfoo.so.2.3.4] File exists

>>>>

>>>> strace shows a similar EEXIST error in a call to symlink.

>>>>

>>>> Thanks,

>>>> Andrew

>>>>

>>>>

>>>

>>> _______________________________________________

>>> Scons-users mailing list

>>> Scons-users at scons.org

>>> http://four.pairlist.net/mailman/listinfo/scons-users

>>>

>>>

>>

>> _______________________________________________

>> Scons-users mailing list

>> Scons-users at scons.org

>> http://four.pairlist.net/mailman/listinfo/scons-users

>>

>>

>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://four.pairlist.net/pipermail/scons-users/attachments/20130527/168ccd03/attachment-0001.html