RFR: JDK-8198862 Stop doing funky compilation stuff for dtrace
erik.joelsson at oracle.com
Fri Mar 2 15:29:47 UTC 2018
This looks good to me.
On 2018-03-02 04:45, Magnus Ihse Bursie wrote:
> On 2018-03-02 12:10, Magnus Ihse Bursie wrote:
>> On 2018-03-02 03:01, David Holmes wrote:
>>> Hi Magnus,
>>> On 1/03/2018 10:48 AM, Magnus Ihse Bursie wrote:
>>>> We're doing a lot of weird compilation stuff for dtrace. With this
>>>> patch, most of the weirdness is removed. The remaining calls to
>>>> $(CC) -E has been changed to $(CPP) to clarify that we do not
>>>> compile, we just use the precompiler.
>>>> One of the changes I made was to actually split up the last and
>>>> final dtrace call into a separate preprocessing step. However, this
>>>> uses the solaris studio preprocessor instead of the ancient system
>>>> preprocessor, which has changed behavior. A string like (&``_var)
>>>> is now expanded to (& ` ` _var), which is not accepted by dtrace.
>>>> :-( I have worked around this by adding the preprocessed output,
>>>> without the spaces, in two places. If anyone wants to dig deeper
>>>> into dtrace script file syntax, or C preprocessor magic, to avoid
>>>> this, let me know... (I'll just state that the "obvious" solution
>>>> of sending -Xs to the preprocessor to get old-style behavior does
>>>> not work: this just makes the solaris studio preprocessor call the
>>>> ancient preprocessor in turn, and we've gained nothing...)
>>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8198862
>>> Why did you rename generateJvmOffsetsMain.c to
>>> generateJvmOffsetsMain.cpp? It isn't a C++ program, it's just a C
>> Yes, but so are generateJvmOffsets.cpp. :-& There was no point in
>> mixing a .cpp and .c file for this trivial build tool helper. In
>> fact, I don't even understand why they are two separate files -- if I
>> get the blessings from someone in hotspot, I'll gladly just
>> concatenate them into a single file.
> Come to think about it, I don't care about the hotspot group's
> blessing. ;-) I just moved the main function into the
> generateJvmOffsets.cpp file. It was just silly having it as a separate
>>> ! # Since we cannot generated JvmOffsets.cpp as part of the
>>> gensrc step,
>>> Comment doesn't read right.
>> Typo, should be "generate". I'll fix.
> I also restored the extra ( ) in ExecuteWithLog with redirection, and
> added an additional ( ) for one case that was previously missing one.
> Finally I also added the changes to dtrace that Erik requested for
> JDK-8198859, but which was already pushed by that time.
> New webrev:
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