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Subject: Re: tcmalloc compatibility
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* Rich Felker <dalias@libc.org> [2018-04-18 16:35:56 -0400]:
> Today I pushed changes which should make malloc
> replacement/interposition work reliably as long as you only use
> AS-safe functions. If you try this, please let us know how it turns
> out and if you run into any unexpected problems.

there was a report on irc that this change in memalign has falsepositives:

-       if (len > SIZE_MAX - align) {
+       if (len > SIZE_MAX - align || free != __internal_free) {

in particular &free can point to a plt entry in the main executable
while &__internal_free is in libc.so so they compare unequal.