Martin Sebor wrote: > This has been bugging me -- when someone checks out trunk, does a build and > sends > us build results, we have no way of telling that the build results are, in > fact, for trunk and > not for 4.2.0 (or the head of 4.2.x), because the value of _RWSTD_VER is the > same. I > think we should change it so that the value is unique for each branch, or at > least distinct > from any release. > > Any suggestions for what would be a good value?
The following is my suggestion for a scheme for _RWSTD_VER: Trunk: 0xFFFFFFFF Trunk feature branch: 0xFFFFFFxx Major branch: 0xMMFF0000 Maintenance branch: 0xMMmmFF00 A trunk feature branch is a branch in subversion used for developing a specific feature, which isn't ready for inclusion in trunk, but is major enough that incremental testing is required. An example could be the implementation of concepts. The placeholder 'xx' is a non-FF value, unique to a feature branch. If the number of feature branches exceeds 255, it will be necessary to reuse numbers, but this isn't a likely occurrence in the near term. These numbers should be issued in the order the branches are created. A major branch is a branch in subversion used for ongoing development of a source compatible lineage. The placeholder MM represents the major version. An example would be ongoing maintenance of the 4.x version of stdcxx beyond 4.3, after the 5.0 release has been made. In the case of a 4.x maintenance branch, the version would be 0x04FF0000 Maintenance branches are an established concept, with the 4.2.x branch being an example. The placeholder MM represents the major version, with the placeholder mm representing the minor version. In the case of 4.2.x, the version would be 0x0402FF00. Justification: My primary reason for using the 0xFF value as a placeholder (generally) is because it is greater than any particular released version number. This should allow checks which look for a specific version of the library (either older or newer) to function correctly. If someone wanted to exclude the trunk from these checks, it would be possible to simply perform a bitwise negation, and if the value of that negation is 0, it means the token references a trunk version. --Andrew Black
