Comme=
nt # 12
on bug 10692=
8
from Roland Scheidegger
(In reply to ubizjak from comment #11)
> The (effectively the same patch as yours) propos=
ed patch would be:
>=20
> diff --git a/src/gallium/drivers/r600/sb/sb_expr.cpp
> b/src/gallium/drivers/r600/sb/sb_expr.cpp
> index 7a5d62c8e8..a609d1377f 100644
> --- a/src/gallium/drivers/r600/sb/sb_expr.cpp
> +++ b/src/gallium/drivers/r600/sb/sb_expr.cpp
> @@ -714,6 +714,8 @@ bool expr_handler::fold_assoc(alu_=
node *n) {
>=20=20
> n->src.resize(2);
> n->bc.set_op(ALU_OP2_ADD);
> + fold_alu_op2(*n);
> + return true;
> }
> } else if (last_arg >=3D 0) {
> n->src[0] =3D a->src[last_arg];
>=20
> WDYT?
I am not quite convinced it's ok to return true (in fold_alu_op3) if the
expression hasn't really been folded. You are quite right that just above it
looks similar, but all other places always return the return value of
fold_alu_op2 when calling into it from fold_alu_op3.
(Not saying it isn't correct, just saying I can't tell...)
> On a side note, maybe -D_GLIBCXX_ASSERTIONS shou=
ld be added to mesa
> testsuite. This is the flag that Fedora 28 builds use by default now, =
so it
> would be beneficial to catch these bugs early in the development cycle,
> before they reach users.
I was actually going to suggest to enable -D_GLIBCXX_DEBUG for debug builds
always, but it wouldn't work in general (due to not being able to link anyt=
hing
which hasn't been compiled with it, for instance llvm). So using
-D_GLIBCXX_ASSERTIONS instead (which should be link-compatible) looks like a
good idea to me, albeit it didn't do anything for me (too old libstdc++ I
suppose). I'm also not quite sure which issues it actually catches (vs the
DEBUG one) but even if it just catches some that should be a plus...