[AMQCPP-158] libtool release and version-info arguments need to be set correctly

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.1.2
• Fix Version/s: 2.2.3

Environment

Debian

• Assignee: Timothy A. Bish
• Reporter: Daniel Pocock
• Created: 14/Dec/07 19:40
• Updated: 31/Dec/08 20:52
• Resolved: 31/Dec/08 20:52

Description

When make is invoked, libtool is asked to build the library with this command line:

/bin/sh ../../libtool --tag=CXX --mode=link g++ -ansi -pedantic -W -Wall -fPIC -fstrict-aliasing -Wstrict-aliasing=2 -Wno-long-long -g -O2 -version-info 2:1:2 -release 2.1.2 -o libactivemq-cpp.la -rpath /usr/lib activemq/core/libactivemq_cpp_la-ActiveMQConsumer.lo ...........

Notice the `-release 2.1.2' argument to libtool? Using a unique release number with each build means that applications will only run with one specific build, and no others.

Perhaps `-release 2' might be more appropriate? This would mean that an application that expects version 2.1.1 would still be willing to link with 2.2.0 (for example) at runtime. Alternatively, it may be better to omit the release argument, and just use version-info.

The -version-info argument allows more fine-grained control - however, it is not meant to be written as MAJOR:MINOR:REVISION. The three values mean `version:revision:age', where:

• version = ABI version, an integer that is increment whenever binary compatibility changes
• revision = implementation (this number is incremented when there is a code change that does not impact the binary interface)
• age = how many previous versions are binary compatible, e.g if age = 2, then version, (version - 1) and (version - 2) are all binary compatible - the age value specified for this library (2) suggests that it is binary compatible to the original version (0).

ABI version numbers are not the same as product version numbers. If the product number is 2.1.2, that does not mean the -version-info argument is 2:1:2.

I have created some pages on the wiki to discuss version and packaging issues; these issues need to be agreed upon by the community before a version scheme can be implemented in the build system.

I am willing to work on the details and contribute a patch for this once there has been some consensus on which is the best versioning scheme to adopt and what level of binary compatibility is expected.

Wiki pages:

http://cwiki.apache.org/confluence/display/AMQCPP/ActiveMQ-CPP+product+version+number

http://cwiki.apache.org/confluence/display/AMQCPP/ActiveMQ-CPP%2C+libtool+and+packaging+notes