[CMake] [PATCH] Optionally skip link dependencies on shared library files

[Leif Walsh]

This is exactly what I wanted, and the results were incredible.  Thank
you.

I'll patch all my installs with this and hope it gets in a public release
soon.

Leif Walsh <leif.walsh at gmail.com> writes:

> Cool, thanks. I'll try this!
>
> Sent from my iPhone
>
> On Oct 26, 2012, at 8:43, Brad King <brad.king at kitware.com> wrote:
>
>> Add target property LINK_DEPENDS_NO_SHARED and initialization variable
>> CMAKE_LINK_DEPENDS_NO_SHARED to enable this behavior.
>> 
>> Suggested-by: Leif Walsh <leif.walsh at gmail.com>
>> ---
>> 
>> On 08/03/2012 04:57 PM, Leif Walsh wrote:
>>> On 3 Aug, 2012, at 4:44 PM, Andreas Pakulat <apaku at gmx.de> wrote:
>>>> Actually no, adding new public API, changing existing API in
>>>> compatible ways are things you can do with a shared library which
>>>> needs relinking.
>>> 
>>> Not without changing the header files, which forces
>>> recompilation.  As the author of a shared library, your header
>>> files are your contract with your clients.
>> 
>> Great point.  Please try this patch on top of 2.8.10-rc3.
>> Then build with -DCMAKE_LINK_DEPENDS_NO_SHARED=1 or add
>> 
>> set(CMAKE_LINK_DEPENDS_NO_SHARED 1)
>> 
>> to the top of your project.
>> 
>> -Brad
>> 
>> Source/cmComputeLinkInformation.cxx |   10 +++++++++-
>> Source/cmComputeLinkInformation.h   |    1 +
>> Source/cmDocumentVariables.cxx      |    9 +++++++++
>> Source/cmTarget.cxx                 |   17 +++++++++++++++++
>> 4 files changed, 36 insertions(+), 1 deletion(-)
>> 
>> diff --git a/Source/cmComputeLinkInformation.cxx b/Source/cmComputeLinkInformation.cxx
>> index cd3ef59..d8ffb5e 100644
>> --- a/Source/cmComputeLinkInformation.cxx
>> +++ b/Source/cmComputeLinkInformation.cxx
>> @@ -277,6 +277,10 @@ cmComputeLinkInformation
>>   this->UseImportLibrary =
>>     this->Makefile->GetDefinition("CMAKE_IMPORT_LIBRARY_SUFFIX")?true:false;
>> 
>> +  // Check whether we should skip dependencies on shared library files.
>> +  this->LinkDependsNoShared =
>> +    this->Target->GetPropertyAsBool("LINK_DEPENDS_NO_SHARED");
>> +
>>   // On platforms without import libraries there may be a special flag
>>   // to use when creating a plugin (module) that obtains symbols from
>>   // the program that will load it.
>> @@ -650,7 +654,11 @@ void cmComputeLinkInformation::AddItem(std::string const& item, cmTarget* tgt)
>> 
>>       // Pass the full path to the target file.
>>       std::string lib = tgt->GetFullPath(config, implib, true);
>> -      this->Depends.push_back(lib);
>> +      if(!this->LinkDependsNoShared ||
>> +         tgt->GetType() != cmTarget::SHARED_LIBRARY)
>> +        {
>> +        this->Depends.push_back(lib);
>> +        }
>> 
>>       this->AddTargetItem(lib, tgt);
>>       this->AddLibraryRuntimeInfo(lib, tgt);
>> diff --git a/Source/cmComputeLinkInformation.h b/Source/cmComputeLinkInformation.h
>> index f60f8d3..e0078af 100644
>> --- a/Source/cmComputeLinkInformation.h
>> +++ b/Source/cmComputeLinkInformation.h
>> @@ -82,6 +82,7 @@ private:
>>   // Configuration information.
>>   const char* Config;
>>   const char* LinkLanguage;
>> +  bool LinkDependsNoShared;
>> 
>>   // Modes for dealing with dependent shared libraries.
>>   enum SharedDepMode
>> diff --git a/Source/cmDocumentVariables.cxx b/Source/cmDocumentVariables.cxx
>> index 8db0e8f..55d70f8 100644
>> --- a/Source/cmDocumentVariables.cxx
>> +++ b/Source/cmDocumentVariables.cxx
>> @@ -1222,6 +1222,15 @@ void cmDocumentVariables::DefineVariables(cmake* cm)
>>      "Variables that Control the Build");
>> 
>>   cm->DefineProperty
>> +    ("CMAKE_LINK_DEPENDS_NO_SHARED", cmProperty::VARIABLE,
>> +     "Whether to skip link dependencies on shared library files.",
>> +     "This variable initializes the LINK_DEPENDS_NO_SHARED "
>> +     "property on targets when they are created.  "
>> +     "See that target property for additional information.",
>> +     false,
>> +     "Variables that Control the Build");
>> +
>> +  cm->DefineProperty
>>     ("CMAKE_AUTOMOC", cmProperty::VARIABLE,
>>      "Whether to handle moc automatically for Qt targets.",
>>      "This variable is used to initialize the "
>> diff --git a/Source/cmTarget.cxx b/Source/cmTarget.cxx
>> index 423b350..9cfcb63 100644
>> --- a/Source/cmTarget.cxx
>> +++ b/Source/cmTarget.cxx
>> @@ -651,6 +651,22 @@ void cmTarget::DefineProperties(cmake *cm)
>>      "custom Makefile link rules.");
>> 
>>   cm->DefineProperty
>> +    ("LINK_DEPENDS_NO_SHARED", cmProperty::TARGET,
>> +     "Do not depend on linked shared library files.",
>> +     "Set this property to true to tell CMake generators not to add "
>> +     "file-level dependencies on the shared library files linked by "
>> +     "this target.  "
>> +     "Modification to the shared libraries will not be sufficient to "
>> +     "re-link this target.  "
>> +     "Logical target-level dependencies will not be affected so the "
>> +     "linked shared libraries will still be brought up to date before "
>> +     "this target is built."
>> +     "\n"
>> +     "This property is initialized by the value of the variable "
>> +     "CMAKE_LINK_DEPENDS_NO_SHARED if it is set when a target is "
>> +     "created.");
>> +
>> +  cm->DefineProperty
>>     ("LINK_INTERFACE_LIBRARIES", cmProperty::TARGET,
>>      "List public interface libraries for a shared library or executable.",
>>      "By default linking to a shared library target transitively "
>> @@ -1314,6 +1330,7 @@ void cmTarget::SetMakefile(cmMakefile* mf)
>>   this->SetPropertyDefault("OSX_ARCHITECTURES", 0);
>>   this->SetPropertyDefault("AUTOMOC", 0);
>>   this->SetPropertyDefault("AUTOMOC_MOC_OPTIONS", 0);
>> +  this->SetPropertyDefault("LINK_DEPENDS_NO_SHARED", 0);
>>   this->SetPropertyDefault("LINK_INTERFACE_LIBRARIES", 0);
>>   this->SetPropertyDefault("WIN32_EXECUTABLE", 0);
>>   this->SetPropertyDefault("MACOSX_BUNDLE", 0);
>> -- 
>> 1.7.10.4
>> 


-- 
Cheers,
Leif