RFR(XXS): 8205916: [test] Fix jdk/tools/launcher/RunpathTest to handle both, RPATH and RUNPATH

[Erik Joelsson]

Looks ok to me.

/Erik


On 2018-06-27 03:26, Volker Simonis wrote:
> Hi,
>
> can I please have a review for the following tiny test fix (I'm
> actually not sure which would be the appropriate mailing list for this
> fix so please redirect if necessary):
>
> http://cr.openjdk.java.net/~simonis/webrevs/2018/8205916/
> https://bugs.openjdk.java.net/browse/JDK-8205916
>
> The test currently only checks for RPATH in the dynamic section of the
> launcher, but some linkers / Linux distributions (notably SLES) use
> RUNPATH instead.
>
> Following are the gory details:
>
> The test jdk/tools/launcher/RunpathTest.java checks that the java
> launcher on Linux and Solaris has the correct RPATH path baked into
> the executable.
>
> Unfortunately, the situation with RPATH is a little weird:
>
>    - in order to bake a runtime path into a dynamically linked library
> or executable one has to use the "-rpath <PATH>" linker option (from
> the C/C++ compiler this is usually available as "-Wl,-rpath,<path>").
>    - depending on the dynamic linker version and Linux distribution,
> the "-rpath" linker option adds either a "RPATH" entry (Ubuntu 16.04,
> RHEL 7.4) or a "RUNPATH" entry (SLES 12.1, SLES 15) or both entries
> together (SLES 11.3) to the dynamic section of the shared
> library/executable.
>    - the semantics of "RPATH" and "RUNPATH" are slightly different:
> "RPATH" is evaluated at runtime before LD_LIBRARY_PATH (if "RUNPATH"
> isn't present) while "RUNPATH" is evaluated after LD_LIBRARY_PATH
> (i.e. RUNPATH can be overridden at runtime by setting
> LD_LIBRARY_PATH).
>    - "RPATH" is considered obsolete and should be replaced by "RUNPATH"
> according to the man-page of "ld.so (8)".
>    - the linker option "--enable-new-dtags"/"--disable-new-dtags" (or
> the corresponding compiler flags
> "-Wl,--enable-new-dtags"/"-Wl,--disable-new-dtags") can be used to
> enforce the generation of "RUNPATH"/"RPATH" respectively (except for
> systems like SLES 11.3 where "--enable-new-dtags" generates both
> "RPATH" and "RUNPATH" while "--disable-new-dtags" only generates
> "RPATH").
>
> But this issue is not about fixing the build so to cut a long story
> short - the test RunpathTest.java should be able to handle both
> runtime path variants equally well. This can be easily achieved by
> extending the match pattern from ".*RPATH.*\\$ORIGIN/../lib.*" to
> ".*R(UN)?PATH.*\\$ORIGIN/../lib.*"
>
> Thank you and best regards,
> Volker