Ensure shared library using MSYS2 for a commercial code

[a-jp]

Hi,

I'd like to use (unmodified) CppAD within a commercial closed source code that I distribute. To comply with EPL2.0 I must (for practical purposes) link to a shared library, as static libraries require me to provide a mechanism for the person at the other end to link to a different version of the cppad libraries if they wish, which is practically very challenging while keeping the source closed.

There is a section in the cmakelists:

IF( is_msys OR is_cygwin OR is_windows )
   IF( NOT cppad_static_lib )
      MESSAGE(WARNING
"This systems uses windows dynamic libraries.
The cppad library must be static for this case.
Ignoring fact that cppad_static_lib is FALSE.
"
      )
   ENDIF( )
   SET(is_cppad_lib_dynamic 0)
ELSE( )
   IF( cppad_static_lib )
      SET(is_cppad_lib_dynamic 0)
   ELSE( )
      SET(is_cppad_lib_dynamic 1)
   ENDIF( )
ENDIF( )

If I'm on MSYS2 and request cppad_static_lib to be false, it will be ignored. Is this something that can be reworked, to allow all cppad libs (including the bindings to ipopt also which I use) to be dynamic rather than static?

On a related note, I see on linux that a shared object will be built, but that libcppad_ipopt seems to always be a static library. Again, is this something that could be changed to always be dynamic?

Many thanks,

[bradbell]

As I recall, *.dll libraries create a separate copy for of the variables that are static in a function, *.so libraries only have one copy for each of these variables.

I suggest you try suppressing the change on MSYS2 and see if the CppAD make checks pass or fail.

[a-jp]

I've made the following changes:

$ git diff
diff --git a/CMakeLists.txt b/CMakeLists.txt
index c7e87cb39..5448cea49 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -573,7 +573,7 @@ Ignoring fact that cppad_static_lib is FALSE.
 "
       )
    ENDIF( )
-   SET(is_cppad_lib_dynamic 0)
+   SET(is_cppad_lib_dynamic 1)
 ELSE( )
    IF( cppad_static_lib )
       SET(is_cppad_lib_dynamic 0)
diff --git a/cppad_ipopt/src/CMakeLists.txt b/cppad_ipopt/src/CMakeLists.txt
index d8673bfbe..7710f1262 100644
--- a/cppad_ipopt/src/CMakeLists.txt
+++ b/cppad_ipopt/src/CMakeLists.txt
@@ -18,7 +18,7 @@ SET(source_list
 )
 # END_SORT_THIS_LINE_MINUS_2

-ADD_LIBRARY(cppad_ipopt ${source_list})
+ADD_LIBRARY(cppad_ipopt SHARED ${source_list})
 set_compile_flags( cppad_ipopt "${cppad_debug_which}" "${source_list}" )

 # install(FILES files... DESTINATION <dir>

I'm a new user to ninja and that is how the code is built. 'make check' is therefore not a command, should I be running 'ninja test'?

[a-jp]

As I recall, *.dll libraries create a separate copy for of the variables that are static in a function, *.so libraries only have one copy for each of these variables.

I'm not sure of the point you're making here. Could you explain?

Thanks

[bradbell]

1. You can run cmake for ninja or make; see generator on
   https://cppad.readthedocs.io/latest/cmake.html#generator

2. Don't worry about my point above for now. Just try the following using a version of
   CMakeLists.txt where is_cppad_lib_dynamic has the value 1 on the target system.

   mkdir build
   cd build
   cmake -G "MSYS Makefiles" ..
   make check

[a-jp]

Ok thanks for that. I've remade your latest tagged version using the suggestion above using the code diff I've already posted. I've attached the full output of make check. There were 10 failures that I can see, all seem to be that the libraries cannot find system libraries, api-ms-win-crt-string-l1-1-0.dll for example. I believe these are windows system libraries. I have not made any attempt to locate these or add them to any paths - I'm not really sure what they are.

Some of the failures include the ipopt tests against your ipopt wrappers - these are the ones I'm making use of so that's the focus. What would you suggestion to fix these build errors?

make_check_output.txt

[bradbell]

Is this a Debug or Release build ? If it is a release, try with debugging for more error messaging.

[a-jp]

release.

/cppad_ipopt_test.exe: error while loading shared libraries: api-ms-win-crt-string-l1-1-0.dll: cannot open shared object file: No such file or directory

will debugging give more info on the missing library?

[bradbell]

release.

/cppad_ipopt_test.exe: error while loading shared libraries: api-ms-win-crt-string-l1-1-0.dll: cannot open shared object file: No such file or directory

will debugging give more info on the missing library?

More info. You can run make check_speed_example because that is the check that is failing (with debug info).

[a-jp]

using -Dcppad_debug_which="debug_all" now fails to actually build:

[100%] Linking CXX shared library libcppad_lib.dll
[100%] Built target cppad_lib
[100%] Building CXX object cppad_ipopt/src/CMakeFiles/cppad_ipopt.dir/vec_fun_pattern.cpp.obj
[100%] Linking CXX shared library libcppad_ipopt.dll
 C:/msys64/ucrt64/bin/../lib/gcc/x86_64-w64-mingw32/14.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: CMakeFiles/cppad_ipopt.dir/objects.a(cppad_ipopt_nlp.cpp.obj): in function `Ipopt::ReferencedObject::ReferencedObject()':
C:/msys64/home/user/codebase/gcc/release/from-git-repo/Ipopt-releases-3.14.16-install/include/coin-or/IpReferenced.hpp:173:(.text$_ZN5Ipopt16ReferencedObjectC2Ev[_ZN5Ipopt16ReferencedObjectC2Ev]+0xb): undefined reference to `__imp__ZTVN5Ipopt16ReferencedObjectE'
C:/msys64/ucrt64/bin/../lib/gcc/x86_64-w64-mingw32/14.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: CMakeFiles/cppad_ipopt.dir/objects.a(cppad_ipopt_nlp.cpp.obj): in function `Ipopt::ReferencedObject::~ReferencedObject()':
C:/msys64/home/user/codebase/gcc/release/from-git-repo/Ipopt-releases-3.14.16-install/include/coin-or/IpReferenced.hpp:177:(.text$_ZN5Ipopt16ReferencedObjectD2Ev[_ZN5Ipopt16ReferencedObjectD2Ev]+0xb): undefined reference to `__imp__ZTVN5Ipopt16ReferencedObjectE'
C:/msys64/ucrt64/bin/../lib/gcc/x86_64-w64-mingw32/14.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: CMakeFiles/cppad_ipopt.dir/objects.a(cppad_ipopt_nlp.cpp.obj): in function `Ipopt::ReferencedObject::~ReferencedObject()':
C:/msys64/home/user/codebase/gcc/release/from-git-repo/Ipopt-releases-3.14.16-install/include/coin-or/IpReferenced.hpp:177:(.text$_ZN5Ipopt16ReferencedObjectD1Ev[_ZN5Ipopt16ReferencedObjectD1Ev]+0xb): undefined reference to `__imp__ZTVN5Ipopt16ReferencedObjectE'
C:/msys64/ucrt64/bin/../lib/gcc/x86_64-w64-mingw32/14.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: CMakeFiles/cppad_ipopt.dir/objects.a(cppad_ipopt_nlp.cpp.obj): in function `Ipopt::TNLP::TNLP()':
C:/msys64/home/user/codebase/gcc/release/from-git-repo/Ipopt-releases-3.14.16-install/include/coin-or/IpTNLP.hpp:61:(.text$_ZN5Ipopt4TNLPC2Ev[_ZN5Ipopt4TNLPC2Ev]+0x1b): undefined reference to `__imp__ZTVN5Ipopt4TNLPE'
C:/msys64/ucrt64/bin/../lib/gcc/x86_64-w64-mingw32/14.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: CMakeFiles/cppad_ipopt.dir/objects.a(cppad_ipopt_nlp.cpp.obj): in function `Ipopt::TNLP::~TNLP()':
C:/msys64/home/user/codebase/gcc/release/from-git-repo/Ipopt-releases-3.14.16-install/include/coin-or/IpTNLP.hpp:65:(.text$_ZN5Ipopt4TNLPD2Ev[_ZN5Ipopt4TNLPD2Ev]+0xf): undefined reference to `__imp__ZTVN5Ipopt4TNLPE'
C:/msys64/ucrt64/bin/../lib/gcc/x86_64-w64-mingw32/14.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: CMakeFiles/cppad_ipopt.dir/objects.a(cppad_ipopt_nlp.cpp.obj): in function `void CppAD::put_check_for_nan<double>(CppAD::vector<double> const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >&)':
C:/msys64/home/user/codebase/gcc/release/from-git-repo/cppad-20250000.2/include/cppad/core/check_for_nan.hpp:177:(.text$_ZN5CppAD17put_check_for_nanIdEEvRKNS_6vectorIT_EERNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE[_ZN5CppAD17put_check_for_nanIdEEvRKNS_6vectorIT_EERNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE]+0x5a): undefined reference to `CppAD::local::temp_file[abi:cxx11]()'
collect2.exe: error: ld returned 1 exit status
make[2]: *** [cppad_ipopt/src/CMakeFiles/cppad_ipopt.dir/build.make:165: cppad_ipopt/src/libcppad_ipopt.dll] Error 1
make[1]: *** [CMakeFiles/Makefile2:4155: cppad_ipopt/src/CMakeFiles/cppad_ipopt.dir/all] Error 2
make: *** [Makefile:136: all] Error 2

make check_speed_example is not built.

[bradbell]

Try adding the directory that contains the missing library to your PATH (windows looks for dlls in its path).

[a-jp]

Ok, so that is to fix the most recent debug build failing that you asked for?

Or that is to fix api-ms-win-crt-string-l1-1-0.dll link errors in release?

Also, do you know where that location of these can typically be found, it's not a dll I've actively installed? Inside MSYS2 or inside windows?

[bradbell]

How did you get Ipopt ? The check for nan error means the directory with the lib_cppad.dll may not be in your path.

[a-jp]

I just downloaded and compiled it from source under the same process/os/compilers etc

[bradbell]

There is an option to have cppad get its optional packages and install them locally; see
https://cppad.readthedocs.io/latest/get_optional.sh.html

[a-jp]

getting a bit lost with what I should try next. do you have any advice on where I could typically find api-ms-win-crt-string-l1-1-0.dll to add to my path?

I will go back to a release build and ensure ipopt is in the path