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Björn Steinbrink a17fb64fce Workaround LLVM optimizer bug by not marking &mut pointers as noalias 
LLVM's memory dependence analysis doesn't properly account for calls
that could unwind and thus effectively act as a branching point. This
can lead to stores that are only visible when the call unwinds being
removed, possibly leading to calls to drop() functions with b0rked
memory contents.

As there is no fix for this in LLVM yet and we want to keep
compatibility to current LLVM versions anyways, we have to workaround
this bug by omitting the noalias attribute on &mut function arguments.
Benchmarks suggest that the performance loss by this change is very
small.

Thanks to @RalfJung for pushing me towards not removing too many
noalias annotations and @alexcrichton for helping out with the test for
this bug.

Fixes #29485
2016-02-10 23:09:47 +01:00
..
back rustc: Add obj_is_bitcode to TargetOptions 2016-02-06 20:56:31 +00:00
save Changed macro spans in CSVs to point to the macro name, bugfixed nested spans 2016-02-03 20:44:53 +13:00
trans Workaround LLVM optimizer bug by not marking &mut pointers as noalias 2016-02-10 23:09:47 +01:00
diagnostics.rs Check unchecked_div|rem's specialisation 2015-10-31 12:22:15 -07:00
lib.rs Remove old #[allow(trivial_casts)] annotations 2016-02-08 09:35:09 -08:00
README.txt Make librustc's markdown README.txt claim to be markdown. 2015-03-20 13:29:13 +01:00

README.txt 

See the README.md in ../librustc.