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author | Marius Strobl <marius@FreeBSD.org> | 2008-06-25 21:04:59 +0000 |
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committer | Marius Strobl <marius@FreeBSD.org> | 2008-06-25 21:04:59 +0000 |
commit | 0d9e99b6ca4f54bf4f902715e8870d9ff19a8afa (patch) | |
tree | 21030df4cb541765bdaedd12c3aa316481b0b10e /sys/conf/kern.mk | |
parent | 1239136645a7d6bb9912541df2128bdd3c26e704 (diff) | |
download | src-0d9e99b6ca4f54bf4f902715e8870d9ff19a8afa.tar.gz src-0d9e99b6ca4f54bf4f902715e8870d9ff19a8afa.zip |
Use "__asm __volatile" rather than "__asm" for instruction sequences
that modify condition codes (the carry bit, in this case). Without
"__volatile", the compiler might add the inline assembler instructions
between unrelated code which also uses condition codes, modifying the
latter.
This prevents the TCP pseudo header checksum calculation done in
tcp_output() from having effects on other conditions when compiled
with GCC 4.2.1 at "-O2" and "options INET6" left out. [1]
Reported & tested by: Boris Kochergin [1]
MFC after: 3 days
Notes
Notes:
svn path=/head/; revision=180011
Diffstat (limited to 'sys/conf/kern.mk')
0 files changed, 0 insertions, 0 deletions