Hello,
In the build-infra project, I have made various minor build speed
improvements for Windows. These mostly affect incremental build
performance, but in certain cases normal builds are also greatly
affected. I find these worth committing to JDK 9 separately.
List of improvements:
* Rewrote DependOnVariable to use "-include" instead of $(shell $(CAT)
...) to read the old variable value from the last make invocation. This
has a pretty big impact on incremental build performance on Windows.
Also started using the file function in make when available (in make
4.0) instead of $(shell $(PRINTF) ...) when writing these files.
* Implemented ListPathsSafely using the file function when available.
Since we require make 4.0 in cygwin, this will usually be the case when
it matters.
* Reduced the number of shell execution in the compiler and link recipes
by joining them together with "; \". When compiling a lot of native
code, this tends to get quite expensive.
Bug: https://bugs.openjdk.java.net/browse/JDK-8136385
Webrev: http://cr.openjdk.java.net/~erikj/8136385/webrev.01/
/Erik
