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From: "hubicka at kam dot mff.cuni.cz" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug driver/100937] configure: Add
 --enable-default-semantic-interposition
Date: Mon, 22 Nov 2021 22:54:53 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D100937

--- Comment #12 from hubicka at kam dot mff.cuni.cz ---
> (The -fno-semantic-interposition thing is probably the biggest performanc=
e gap
> between gcc -fpic and clang -fpic.)
Yep, it is often confusing to users (who do not understand what ELF
interposition is) that clang and gcc disagree on default flags here.
Recently -Ofast was extended to imply -fno-semantic-interposition that
will hopefully make more people notice this.

While doing that I have added per-symbol flag about interposition to the
symbol table, so we can also support=20

__atttribute__ ((semantic_interposition))

and

__attribute__((no_semantic_interpoition))

if that would be useful for something.=