Thread: pgsql: Mark x86's memory barrier inline assembly as clobbering the cpu

pgsql: Mark x86's memory barrier inline assembly as clobbering the cpu

From
Andres Freund
Date:
Mark x86's memory barrier inline assembly as clobbering the cpu flags.

x86's memory barrier assembly was marked as clobbering "memory" but
not "cc" even though 'addl' sets various flags. As it turns out gcc on
x86 implicitly assumes "cc" on every inline assembler statement, so
it's not a bug. But as that's poorly documented and might get copied
to architectures or compilers where that's not the case, it seems
better to be precise.

Discussion: 20140919100016.GH4277@alap3.anarazel.de

To keep the code common, backpatch to 9.2 where explicit memory
barriers were introduced.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/e5603a2f35baa0bc9d61b16373383fdd37e49509

Modified Files
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src/include/storage/barrier.h |    4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)