Oct 06, 2008
First release using the release procedure

January 28, 2009
version 1.7.0
Added support for Xcode build system version 3 (Mac OS X).
Enhanced generation of flat makefile on Unix.
Added protection against targets with the same name.

February 10, 2009
version 1.7.2
Enhanced analysis of library-to-library dependencies

February 12, 2009
version 1.7.3
Added possibility to specify USR_DEP macro in the toolkit makefiles
to enforce static library build order.

February 27, 2009
version 1.7.4
Corrected assembling DLLs in case of multiple projects with the same name
Added 'rootdir' macro in ptb.ini
Corrected DLL dependency analysis when working with import_project Windows script

March 23, 2009
version 1.7.5
Produce list of generated and updated files.
Optimize UNIX flat makefile to avoid attempts to build each project more than once.
Check and exclude unneeded external projects.

March 27, 2009
version 1.7.6
Bug fix: Corrected generation of unique build id in Unix flat makefile.

April 21, 2009
version 1.8.0
Added generation of check commands lists on Xcode.
Added possibility to specify target platform in command line.
Modified generation of unique build id in Unix flat makefile to calculate it
only once when building multiple targets.
Added generation of Products group on Xcode.
Added support of WATCHERS macro
Merge Compiler.PreprocessorDefinitions defined in project and meta-msvc files.

May 06, 2009
version 1.8.1
Corrected definition of NCBI_SIGNATURE on Xcode 
Modified special handling of LibChoices on Unix

June 10, 2009
version 1.9.0
Modified handling of ComponentChoices on Windows.
Added processing of WSDL_PROJ macro in makefiles.
Made it find Makefile.*.mk in 'src' tree
and take into account macros defined there;
also, find ncbiconf.*.h and include them into generated
ncbiconf_msvc_site.h.
Modified generation of makefile on Unix to avoid multipication
of 'jobserver-fds' argument in parallel builds.

July 13, 2009
version 1.10.0
Added possibility to customize locations of 3rd-party and NCBI C Toolkit libraries
without editing project_tree_builder.ini

August 07, 2009
version 1.11.0
Made it possible to modify parts of NCBI_SIGNATURE from project_tree_builder.ini

October 29, 2009
version 2.0.0
Enforce existence of projects listed in ASN_DEP and USR_DEP
(fail when such project cannot be found).
Added communication mechanism for PTBGUI and reading command line arguments from a file.
Allow hierarchical project tag definition.

November 16, 2009
version 2.1.0
Corrected DLL dependencies analysis

December 01, 2009
version 2.2.0
Added possibility to use previously saved configuration settings

December 14, 2009
version 2.3.0
Added support of logical expressions when specifying project tags filter

January 21, 2010
version 2.4.0
Changed processing of custom metadata to scan the whole source tree for such files.
Modified generation of Unix makefile to allow for better parallelism.

March 15, 2010
version 2.5.0
Added special project type to allow pre-generation of serialization classes
during configuration stage

March 25, 2010
version 2.5.1
Added option to request generation of dependencies on datatool.

April 06, 2010
version 2.6.0
Reduced the number of warning messages, eliminated identical ones.
Added possibility to define precompiled header settings locally.

May 12, 2010
version 2.7.0
Modified Xcode project generation to make it re-link applications
when dependent libraries are changed and to clean helper files
when cleaning CONFIGURE project.
Added possibility to define precompiled header settings in makefiles.

June 02, 2010
version 2.7.1
Corrected file dependencies in Xcode project targets which use
ASN.1 data specifications

July 30, 2010
version 3.0.0
Added support of MSVC 2010

September 02, 2010
version 3.0.1
Fixed bug in list of generated files

September 29, 2010
version 3.1.0
Fixed to mark implied projects as expendable if everything that depends on them is.
Added support of optional user requests (macro definitions).
Corrected project that generates C++ code to remove unneeded specifications.

November 16, 2010
version 3.1.1
Corrected to exclude configurable defines from list of libraries.

November 22, 2010
version 3.1.2
Enable absolute path when specifying subtree.
Changed the way Linker AdditionalOptions are handled.

December 16, 2010
version 3.2.0
Added possibility of defining CharacterSet in makefiles.
Added support of Unicode build configurations.
Corrected generation of configuration header files.
Corrected location of generated Utility projects for MSVC2010.

December 20, 2010
version 3.2.1
Bug fix release

December 28, 2010
version 3.2.2
Take into account Unicode settings when processing 3rd party libraries settings.
Added possibility to add Unicode configurations by default.

February 23, 2011
version 3.3.0
Improved the way project tree builder processes localization macros.
In 3rd party library description, extended the meaning of FILES to include alternatives.

February 25, 2011
version 3.3.1
Corrected handling of INCLUDE directives on XCode.

April 08, 2011
version 3.4.0
Added possibility to collect settings from several makefiles.
Changed build settings to give each project its own intermediate directory and
to create disabled dummy build configuration when it should be omitted in fact.
Corrected handling of unresolved macros.
Make PTB look into src/build-system for custom metadata.
Tuned up manifest generation.

May 17, 2011
version 3.5.0
Corrected checking UserRequests in project requirements.
Modified generation of Unix flat makefile to mark excluded projects as ones
whose build errors can be ignored.
Added possibility to use configurable macros in DLL dependencies description.

October 14, 2011
version 3.6.0
Enhanced generation of Unix makefile to obviate slowdown due to locking.
Added possibility to assign project tags to DLL projects.
Added possibility to access list of enabled features from programs.
Made it possible to generate flat makefile on Unix when importing projects.
Enhanced GUI tool to show list of default project tags - from the current LST file.

October 18, 2011
version 3.6.1
In folder targets of Unix makefile, removed subdirectories with projects excluded from the build.

November 29, 2011
version 3.7.0
Added support of automatic and composite project tags, and tag-based build targets.
Added support of Objective-C source files on MacOSX.
Added support for Xcode build system version 4.

December 07, 2011
version 3.7.1
Changed to always use absolute paths when referencing 3rd party libraries.
