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2 commits

Author SHA1 Message Date
René Scharfe 76dd98c139 remove unnecessary check before QSORT
Add a semantic patch for removing checks similar to the one that QSORT
already does internally and apply it to the code base.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-29 15:42:18 -07:00
René Scharfe dbc540c7a5 add QSORT
Add the macro QSORT, a convenient wrapper for qsort(3) that infers the
size of the array elements and supports the convention of initializing
empty arrays with a NULL pointer, which we use in some places.

Calling qsort(3) directly with a NULL pointer is undefined -- even with
an element count of zero -- and allows the compiler to optimize away any
following NULL checks.  Using the macro avoids such surprises.

Add a semantic patch as well to demonstrate the macro's usage and to
automate the transformation of trivial cases.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-29 15:42:18 -07:00