Change various Gin*Is* macros to return 0/1.
Returning the direct result of bit arithmetic, in a macro intended to be
used in a boolean manner, can be problematic if the return value is
stored in a variable of type 'bool'. If bool is implemented using C99's
_Bool, that can lead to comparison failures if the variable is then
compared again with the expression (see ginStepRight() for an example
that fails), as _Bool forces the result to be 0/1. That happens in some
configurations of newer MSVC compilers. It's also problematic when
storing the result of such an expression in a narrower type.
Several gin macros have been declared in that style since gin's initial
commit in 8a3631f8d86.
There's a lot more macros like this, but this is the only one causing
regression test failures; and I don't want to commit and backpatch a
larger patch with lots of conflicts just before the next set of minor
releases.
Discussion: 20150811154237.GD17575@awork2.anarazel.de
Backpatch: All supported branches
Branch
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REL9_4_STABLE
Details
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http://git.postgresql.org/pg/commitdiff/6faea0169082b4218588e575c3db8b26458664df
Modified Files
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src/include/access/gin_private.h | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
