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So I've made a breakthrough. The memory corruption is due to both parts of the CMOV optimization under OptPass2Jcc, not my Jcc addition (although it might have unintentionally accentuated it). The first part sets p to a dangling pointer, while the 2nd part is a little more complicated, but I'll try to spell everything out once I finish testing my new patch and see if I've eliminated all of my crashes<br>
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</div><div>Gareth<br>
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<span style="font-weight: bold;">On Fri 29/06/18 10:05 , "J. Gareth Moreton" gareth@moreton-family.com sent:<br>
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It turns out that it's invalid memory. Trying to call "ClassName" raises an access violation (other aligns work fine). There's a dangling pointer somewhere. I found one in the CMOV optimisation code, but that hasn't fixed the crash.<br>
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</div><div>Gareth</div><div><br>
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<span style="font-weight: bold;">On Fri 29/06/18 10:27 , Martok listbox@martoks-place.de sent:<br>
</span><blockquote style="BORDER-LEFT: #F5F5F5 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px; PADDING-RIGHT: 0px"><span style="color: rgb(102, 102, 102);">> A clue that leads me to believe there's internal corruption is that a produced
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<span style="color: rgb(102, 102, 102);">> .s file yields an alignment field of ".balign 119,0x90", which should never
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<span style="color: rgb(102, 102, 102);">> happen.
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Could you set a breakpoint on aggas.pas:721 (the call to doalign) with a
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conditional on "tai_align_abstract(hp).aligntype=119" and check what the actual
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type of hp is? It could be that at some point a node gets its typ changed in an
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invalid way?
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aligntype should be either one of 2^[0..5], never something else...
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This is where AddressSanitizer support would be *nice*.
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--
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Regards,
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Martok
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Ceterum censeo b32079 esse sanandam.
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