> On Jun 2, 2017, at 9:14 AM, Ioi Lam <ioi....@oracle.com> wrote: > > On 6/2/17 8:44 AM, Ioi Lam wrote: >> >> On 6/2/17 6:40 AM, Chris Hegarty wrote: >>> On 02/06/17 00:14, Ioi Lam wrote: >>>> ... >>>> >>>> The gem is hidden in the compile.0.jta file. It contains something like: >>>> >>>> -sourcepath <blahblah>:/jdk/foobar/test/lib:<blahblah> >>>> >>>> So if my test refers to a class under /test/lib, such as >>>> jdk.test.lib.process.ProcessTools, javac will be able to locate it under >>>> /jdk/foobar/test/lib/jdk/test/lib/process/ProcessTools.java, and will >>>> build it automatically. >>>> >>>> So really, there's no reason why the test must explicitly do an @build >>>> of the library classes that it uses. >>> >>> Sure, you're relying on the implicit compilation of dependencies >>> by javac. Look at the output, where it compiles the library >>> classes to. It is part of the classes directory for the >>> individual test. That means that the library classes will need >>> to be compiled many many times. The @build tag will compile >>> the library classes to a common output directory, where they >>> can be reused ( unless I'm missing something ). >>> >>> -Chris. >> Yes, @build will compile classes so that they can be reused. But why should >> it be the responsibility of every test to do this? >> >> To reuse my malloc metaphore -- is it reasonable for every program that uses >> malloc to explicitly build libc? >> >> By the way, jtreg arranges the output directory of the test by the directory >> they sit in, so >> >> jdk/test/foo/bar/XTest.java >> jdk/test/foo/bar/YTest.java >> >> will all output their .class files to the same directory. Therefore, the >> amount of duplicated classes is not as bad as you might think. We've been >> omitting the @build tags in the hotspot tests and we haven't seen any >> problems. >> >> - Ioi > To avoid repeat compilation of the library classes, a more reasonable > solution would be: > > [1] Before test execution -- scan all the selected test to find all libraries > specified by @library tags > > [2] Fully compile all the libraries into their own output directories > > [3] Then, start execution of the selected tests
unfortunately, it is not that simple, there are at least 2 problems w/ that approach: 1. some of library classes have extra module dependency, e.g. jdk.test.lib.management.* depend on jdk.management module, ExtendedRobot (from jdk/test/testlibrary) depends on java.desktop. so compiling the whole library will require extra module dependency, which might be unneeded for the selected tests, as a result we won't be able to run these tests on configurations w/ limited module set. 2. to make our tests packagefull, we had to add '@library /' to many hotspot/test/compiler tests, so we will have to compile all files from hotspot/test. my take on all of this is that determination of output directory for classes is buggy, it uses directory of a @build or @run target to decide where put all produced classes files, but it should have mapping between source and destination paths instead, so all classes from jdk/test/foo/bar/ will go to a test scratch directory and all classes from /test/lib/ (assuming they are declared as @library) and /jdk/test/lib/ to different common directories which will be later added to classpath for the tests which use these libraries. Thanks, -- Igor
