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Diffstat (limited to 'devel-docs/libtool-instructions.txt')
| -rw-r--r-- | devel-docs/libtool-instructions.txt | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/devel-docs/libtool-instructions.txt b/devel-docs/libtool-instructions.txt new file mode 100644 index 0000000..1040a12 --- /dev/null +++ b/devel-docs/libtool-instructions.txt @@ -0,0 +1,65 @@ +configure.ac libtool settings +============================= + +This is a brief description of how the various version variables at the +top of configure.ac are to be set, including gimp_interface_age and +gimp_binary_age. + +See the arithmetic under the "libtool versioning" comment heading in +configure.ac as a reference. + +See https://www.gnu.org/software/libtool/manual/html_node/Libtool-versioning.html +for definitions of libtool "current", "revision" and "age" numbers as +used below. + +When making a release +--------------------- + +(1) When making releases on the stable branch, set: + gimp_micro_version += 1; + gimp_interface_age += 1; + + If gimp_binary_age is defined as a constant, set gimp_binary_age += 1; + else if gimp_binary_age is defined as an m4_eval(), leave it as it is. + + The default gimp_binary_age m4_eval() expression auto-increments + itself. + +(2) NEVER increment gimp_interface_age and gimp_binary_age by more than +1 at any time for whatever reason, or you will have to wear a brown +paper bag on your head to hide your face for the rest of your life. If +you increment gimp_interface_age by more than 1, then the libtool +"current" number is decremented which could result in incompatible +library interface with existing bin programs. + +(3) If any functions have been added, set gimp_interface_age=0. This +will cause the "current" and "age" part of libtool version to bump +upwards, increasing the interface number the library implements while +keeping the minimum interface number supported the same as before +(i.e., backwards compatible ABI). + + Example: In GIMP 2.8.10, with gimp_minor_version=8, + gimp_micro_version=10 and gimp_interface_age=10 (incremented by 1 + for every micro release), current=800 and age=800, which means that + the libraries support interface numbers 0 through 800, and the + interface DID NOT change at all between GIMP 2.8.0 to GIMP 2.8.10. + + Example: In GIMP 2.8.12, with gimp_minor_version=8, + gimp_micro_version=12 and gimp_interface_age=0, current=812 and + age=812, which means that the libraries support interface numbers 0 + through 812, and the ABI interface DID change in backwards + compatible manner at the time gimp_interface_age was set to 0. + +(4) If backwards compatibility was broken, set gimp_binary_age=0 and +gimp_interface_age=0. This will cause "age" part of libtool version to +be 0, increasing the minimum interface supported to "current" part of +libtool version, and making ABI backwards incompatible (the linker +will not be able to use these libraries with programs compiled to work +against older libraries. + + Example: In GIMP 2.8.14, with gimp_minor_version=8, + gimp_micro_version=14, gimp_binary_age=0 and gimp_interface_age=0, + current=814 and age=0, which means that the libraries support + interface number 814 only, which tells libtool the ABI interface + changed in backwards incompatible manner at the time + gimp_binary_age was set to 0. |