Keep lvalue category on structs when evaluating ternary operator

master
Vlad Vissoultchev 2016-03-13 04:32:18 +02:00
parent 32755dbea9
commit 9d778c7bb6
1 changed files with 17 additions and 4 deletions

View File

@ -4536,7 +4536,7 @@ static void expr_lor(void)
static void expr_cond(void)
{
int tt, u, r1, r2, rc, t1, t2, bt1, bt2;
int tt, u, r1, r2, rc, t1, t2, bt1, bt2, islv;
SValue sv;
CType type, type1, type2;
@ -4655,10 +4655,17 @@ static void expr_cond(void)
(t2 & (VT_BTYPE | VT_UNSIGNED)) == (VT_INT | VT_UNSIGNED))
type.t |= VT_UNSIGNED;
}
/* keep structs lvalue by transforming `(expr ? a : b)` to `*(expr ? &a : &b)` so
that `(expr ? a : b).mem` does not error with "lvalue expected" */
islv = (vtop->r & VT_LVAL) && (sv.r & VT_LVAL) && VT_STRUCT == (type.t & VT_BTYPE);
/* now we convert second operand */
gen_cast(&type);
if (VT_STRUCT == (vtop->type.t & VT_BTYPE))
if (islv) {
mk_pointer(&vtop->type);
gaddrof();
}
else if (VT_STRUCT == (vtop->type.t & VT_BTYPE))
gaddrof();
rc = RC_INT;
if (is_float(type.t)) {
@ -4682,12 +4689,18 @@ static void expr_cond(void)
/* put again first value and cast it */
*vtop = sv;
gen_cast(&type);
if (VT_STRUCT == (vtop->type.t & VT_BTYPE))
if (islv) {
mk_pointer(&vtop->type);
gaddrof();
}
else if (VT_STRUCT == (vtop->type.t & VT_BTYPE))
gaddrof();
r1 = gv(rc);
move_reg(r2, r1, type.t);
vtop->r = r2;
gsym(tt);
if (islv)
indir();
}
}
}