armv7: drop alloca from libc
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Authored by brooks on Mon, Apr 28, 9:06 PM.

Details

Reviewers

imp
manu
kib
andrew

Summary

The alloca() interface has been a macro expanding to __builtin_alloca()
since 2003 (commit 79806b4cdce0, included in FreeBSD 5.2). As such, no
correct program linked to this symbol on any shipped arm release (arm
was added in 6.0).

Between this and armv7's Tier-2 status, remove this implementation
entierly.

Diff Detail

Repository

rG FreeBSD src repository

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Lint Passed

Unit

No Test Coverage

Build Status

Buildable 63758
Build 60642: arc lint + arc unit

Event Timeline

brooks created this revision.Mon, Apr 28, 9:06 PM

Herald added a reviewer: andrew. · View Herald TranscriptMon, Apr 28, 9:06 PM

brooks requested review of this revision.Mon, Apr 28, 9:06 PM

Harbormaster completed remote builds in B63758: Diff 154418.Mon, Apr 28, 9:06 PM

brooks added a child revision: D50055: alloca.3: move to share/man/man3.Mon, Apr 28, 9:06 PM

imp accepted this revision.Mon, Apr 28, 10:29 PM

This revision is now accepted and ready to land.Mon, Apr 28, 10:29 PM

Correct or not, we must provide the symbol forever since it is present in the stable version map.

If this were i386 or amd64 then yes, but armv7 is a tier-2 architecture so we can break the ABI contract in ways that are harmless. IMO there's lots of value in making lower tier platforms less weird.