BUILD_SHARED_LIBS & POCO_STATIC cause #pragma comment(lib, "PocoUtil" POCO_LIB_SUFFIX) to be invalid

[athaa]

Hello Poco Team,

Describe the bug
The visual studio compiler/linker ask for Foundation.lib instead of Foundationmd.lib

To Reproduce
I build poco from source, as static, with cmake, using BUILD_SHARED_LIBS =OFF. I keep MT=OFF (to use system/compiler dll).
I got files ending with md.lib and mdd.lib => this is what I expected

I add lib and include dependencies to my project (visual studio) using cmake
I add
#include "Foundation.h"
in the main

call compiler OK
call linker NOT OK

Expected behavior

The linker shoud ask for PocoFoundationmd.lib, not for :
Logs

LINK : fatal error LNK1104: cannot open file 'PocoFoundation.lib'

Please add relevant environment information:

• Windows 10
• POCO 13.3, from what I can see the same problem should apply to the last version (main)

Additional context
From what I can see it is due to the check performed in Foundation.h

#if defined(_WIN32) && defined(_DLL)
	#if !defined(POCO_DLL) && !defined(POCO_STATIC)
		#define POCO_DLL
	#endif
#endif

It cause the following:
#pragma comment(lib, "PocoUtil" POCO_LIB_SUFFIX)
To be invalid (and all similar #pragma) since POCO_LIB_SUFFIX is created using POCO_DLL.

I supposed it should not use POCO_STATIC here because it is deprecated according the cmakefile:
message(WARNING "POCO_STATIC has been deprecated. Please use BUILD_SHARED_LIBS=NO to build static libraries.")
, but use BUILD_SHARED_LIBS (or a combination of both until complete removal)

BTW, I know the documentation :https://docs.pocoproject.org/current/99150-WindowsPlatformNotes.html
ask to use POCO_STATIC, but I guess the code is supposed to be more up to date. I'm right ?

Sorry if I miss something obvious.

Thanks by advance,

Have a good day

[matejk]

Dear @athaa, can you test if the changes on the branch 4754-cmake-windows-static-build (PR #4762) solve the problem?

[athaa]

Dear Matejk,
Thank you
I don't have time to test righ now.
But I will surely give you feedback about your new branch.

[athaa]

Ok I just tested and the behaviour is the same. The linker is still asking for 'PocoFoundation.lib' and not 'PocoFoundationmd.lib'

Can you clarify one point:
The generated include folder is dependent on what option you choose (not the same folder size).
But does it set POCO_STATIC or BUILD_SHARED_LIBS ? It is what I assume.
Or does I have to set it manually in the final appplication build configuration ?

[matejk]

So, if I understand correctly, you

1. build and install Poco
2. build your project using CMake by including provided Poco CMake files

Is this correct?

[athaa]

not sure what you mean exactly by "Poco CMake files", I

1. build and install Poco using provided cmake (which generate visual studio solution)
2. build my project using my own cmake (which generate visual studio solution). In my cmake I use :

target_include_directories(${PROJECT_NAME}
        ...
	PUBLIC ${POCO_INCLUDE_DIR}
)

and:

target_link_libraries(${PROJECT_NAME}
	PUBLIC "$<$<CONFIG:Debug>:${POCO_LIBS_DEBUG}>$<$<CONFIG:Release>:${POCO_LIBS_RELEASE}>" 
	iphlpapi
	ws2_32
)

But the target link library configuration seems useless for Poco due to #pragma comment(lib, "PocoXXX" POCO_LIB_SUFFIX) presence in header file.

It has to be noted that currently I have fixed the linker issue defining POCO_STATIC in my project build configuration (not in POCO build where I use BUILD_SHARED_LIBS=OFF).
Im not sure what will be the way to use it when you will definitively switch to BUILD_SHARED_LIBS ?
Maybe I missunderstand what you intent to do with BUILD_SHARED_LIBS/ POCO_STATIC...

[matejk]

@athaa, when installing Poco after compiling it creates CMake files that you shall use in your project to use Poco with CMake using find_package like:

find_package(Poco REQUIRED COMPONENTS Foundation Net)

Poco CMake files are generated according to the specified configuration, including BUILD_SHARED_LIBS.

If compiling and linking using this way doesn't work properly then we shall investigate the cause.