I would like to have sorts added to Demo.gmk too. I just hit a case
where it caused a difference for me between old build and build-infra.
/Erik
On 2012-09-06 06:08, Kelly O'Hair wrote:
Need a reviewer for this change.
http://cr.openjdk.java.net/~ohair/openjdk8/jdk8-this-file/webrev/
It does change source, but it's effectively a build change.
The goal here is to try and create more predictable binary files and remove the
possibility that
a full source path (via __FILE__) gets baked into the shared libraries or
executables shipped.
So two changes:
* sort the .o files during links so they are always provided to the linker
in the same order.
* replace use of __FILE__ to the macro THIS_FILE with just the basename of
the source file being compiled
The __FILE__ issue is that it has an implementation defined string literal
value, depending on the compiler
and the filename supplied on the compile line. By changing to the new THIS_FILE
macro, the object files
will always have a consistent string literal in them, making it easier to
compare binaries between builds.
Something we have never been able to do in the past. Granted it's just the
basename for the file, but should be enough.
The tricky part is that __FILE__ only gets evaluated when it is used. In normal
C code, it will appear in
macros but it only will get evaluated in the source file being compiled. It is
rare that macros using
__FILE__ will get expanded in include files and I detected this not happening
in the jdk source at all.
-kto
