Fix 0-sized CGemV with unitialized memory #1719
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ricardoV94
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This is failing in the CI and isn't used?
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aseyboldt
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Nov 11, 2025
| } else | ||
| { | ||
| // Empty A matrix, just scale y by beta | ||
| if (dbeta != 1.0) |
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then you get the initial y. We don't create gemv with uninitialized y when dbeta!=0
That would show up in y = y * beta + A @ x * alpha. You get whatever the user y was. Multiplying by 1 wouldn't change it
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Or I may have missed the motivation for your question. This is an eager optimization the theano guys had, do you think it's silly?
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Ah of course. 🤦
Looks good to me, except for the test failure then.
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It's just the unrelated torch module or did miss another?
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Closes #1716
It seems like I this one is on me. I removed the else branch in 709f745 and we didn't have any test that failed.
These functions are not trivial to setup correctly. This is like the 3rd or 4th bug I remember fixing (and apparently causing) and we still have #1262