> I know this document and I think the part on ChangeLog doesn't achieve > its purpose: > > http://www.gnu.org/prep/standards/standards.html#Change-Logs > > Keep a change log to describe all the changes made to program source > files. The purpose of this is so that people investigating bugs in the > future will know about the changes that might have introduced the bug. > Often a new bug can be found by looking at what was recently changed. > More importantly, change logs can help you eliminate conceptual > inconsistencies between different parts of a program, by giving you a > history of how the conflicting concepts arose and who they came from.
Could you elaborate? > When you fix a bug by changing a constant (for example if there has been > an offset by one error or, as I did a few minutes ago in > config/sh/sh.md, there was an error in the argument to consider), this > doesn't always mandate a comment in the code. For example, I think a > description such as the one I wrote when describing the problem > > cmpgeusi_t splitting code compares operand 0 to 0, while this constant > value can only be in operand 1. When compiling the Ada runtime, this > leads to a "cmp/hs #0,r7" instruction which is not valid as "cmp/hs" > operands must be two registers. > > along with the above change would have been a better commit message than > just > > gcc/ > * config/sh/sh.md (cmpgeusi_t): Fix condition. > > which I used as suggested. Not really in my opinion, it's a trivial fix and totally unrelated to Ada in itself, "Fix typo" or "Fix obvious mistake" would have been just fine too. -- Eric Botcazou