| AsmDecl ::= |
|---|
.ver Int32 ':' Int32 ':' Int32 ':' Int32 |
| | … |
The version number of an assembly is specified as four 32-bit integers. This version number shall be captured at compile time and used as part of all references to the assembly within the compiled module.
All standardized assemblies shall have the last two 32-bit integers set to 0. This standard places no other requirement on the use of the version numbers, although individual implementers are urged to avoid setting both of the last two 32-bit integers to 0 to avoid a possible collision with future versions of this standard.
Future versions of this standard shall change one or both of the first two 32-bit integers specified for a standardized assembly if any additional functionality is added or any additional features of the VES are required to implement it. Furthermore, future versions of this standard shall change one or both of the first two 32-bit integers specified for the mscorlib assembly so that its version number can be used (if desired) to distinguish between different versions of the Execution Engine required to run programs.
[Note: A conforming implementation can ignore version numbers entirely, or it can require that they match precisely when binding a reference, or it can exhibit any other behavior deemed appropriate. By convention:
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The first of these 32-bit integers is considered to be the major version number, and assemblies with the same name, but different major versions, are not interchangeable. This would be appropriate, for example, for a major rewrite of a product where backwards compatibility cannot be assumed.
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The second of these 32-bit integers is considered to be the minor version number, and assemblies with the same name and major version, but different minor versions, indicate significant enhancements, but with the intention of being backwards compatible. This would be appropriate, for example, on a "point release" of a product or a fully backward compatible new version of a product.
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The third of these 32-bit integers is considered to be the build number, and assemblies that differ only by build number are intended to represent a recompilation from the same source. This would be appropriate, for example, because of processor, platform, or compiler changes.
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The fourth of these 32-bit integers is considered to be the revision number, and assemblies with the same name, major and minor version number, but different revisions, are intended to be fully interchangeable. This would be appropriate, for example, to fix a security hole in a previously released assembly.
end note]