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Opened 7 years ago

Closed 7 years ago

#368 closed defect (fixed)

HEFT in Amegic broken

Reported by: silvan Owned by: Stefan Hoeche
Priority: major Milestone: rel-2.2.1
Component: ME Generator Version: 2.2.1
Keywords: Cc:

Description

The attached very simple gg->H run card produces a crash during process initialization with Amegic

Attachments (2)

Run.dat (341 bytes) - added by silvan 7 years ago.
run card
amegic_point.diff (645 bytes) - added by silvan 7 years ago.

Download all attachments as: .zip

Change History (6)

Changed 7 years ago by silvan

Attachment: Run.dat added

run card

comment:1 Changed 7 years ago by silvan

Component: Hadron DecaysME Generator
Owner: changed from Frank Siegert to Stefan Hoeche

comment:2 Changed 7 years ago by marek

Resolution: worksforme
Status: newclosed

Hi Silvan,

please use the setup in the examples. The crash is most likely due to the LOOSE_METS scale setter, which is used in integration when specifying METS.

Please reopen if necessary. Cheers, Marek

comment:3 Changed 7 years ago by silvan

Resolution: worksforme
Status: closedreopened

This seems to be platform/compiler specific. I can reproduce it with the example run cards using gcc 6.3.1. The problem occurs in AMEGIC::Point::FindOrder, where a check 'if (!this)' is implemented. That seems to work with older compilers but in general causes undefined behaviour, I believe. I attached a patch that (I think) solves this issue. Could someone with better knowledge of Amegic check if it doesn't break anything?

Last edited 7 years ago by silvan (previous) (diff)

Changed 7 years ago by silvan

Attachment: amegic_point.diff added

comment:4 Changed 7 years ago by marek

Resolution: fixed
Status: reopenedclosed

Ah, right. Yes, this is compiler specific. Newer gcc (>6) versions assume that "if (this)" is always true and optimise it away. For some reason (sloppy programming?) this not always true here. Holger fixed this issue in r29425 which went into rel-2-2-2. CMS also recently stumbled over this.

Cheers, Marek

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as closed The owner will remain Stefan Hoeche.

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