On Fri, 13 Dec 2024 05:46:28 GMT, Jan Lahoda <jlah...@openjdk.org> wrote:
> The microbenchmarks build generates a considerable amount of (generated) > sources using an annotation processor. This, by itself, is not a problem. > But, it generates them into the class output, and after the microbenchmarks > build has been updated to be (somewhat) incremental, the class output has > been added to the classpath(*): > https://github.com/openjdk/jdk/commit/b704bfa205bbd8c56f128ce5d727d40c8a3ec613 > > Then when the AP attempts to generate a new file (for a class name), javac > will look for same-named classes on the classpath, and may load the source > code generated by a previous rounds of builds, in case of an incremental > build. And since the AP generates the considerable amount of these files, > this leads to loading a considerable amounts of source code, eventually > leading to memory problems > ([JDK-8345302](https://bugs.openjdk.org/browse/JDK-8345302)). > > The proposal herein is to split the (generated) source output from the class > output. This considerably reduces the amount of memory javac uses, and > generally seems like a good approach for the build. > > (*) adding the class output to the classpath is usually needed when > incrementally compiling code in the unnamed module, to ensure that if e.g. > only one source file is being compiled, it can refer to other, already > produced, classes. As a side note, this does not need to be done in > named-module compilation modes, as javac automatically reads the class output > when compiling the named modules. But it is not easily possible to enhance > javac to do that for unnamed module, due to compatibility concerns. Marked as reviewed by erikj (Reviewer). ------------- PR Review: https://git.openjdk.org/jdk/pull/22731#pullrequestreview-2502373685
