diff options
Diffstat (limited to 'op.c')
| -rw-r--r-- | op.c | 8 |
1 files changed, 7 insertions, 1 deletions
@@ -677,10 +677,14 @@ Perl_scalarvoid(pTHX_ OP *o) else { if (ckWARN(WARN_VOID)) { useless = "a constant"; + /* don't warn on optimised away booleans, eg + * use constant F, 5; Foo || print; */ + if (cSVOPo->op_private & OPpCONST_SHORTCIRCUIT) + useless = 0; /* the constants 0 and 1 are permitted as they are conventionally used as dummies in constructs like 1 while some_condition_with_side_effects; */ - if (SvNIOK(sv) && (SvNV(sv) == 0.0 || SvNV(sv) == 1.0)) + else if (SvNIOK(sv) && (SvNV(sv) == 0.0 || SvNV(sv) == 1.0)) useless = 0; else if (SvPOK(sv)) { /* perl4's way of mixing documentation and code @@ -3363,11 +3367,13 @@ S_new_logop(pTHX_ I32 type, I32 flags, OP** firstp, OP** otherp) if ((type == OP_AND) == (SvTRUE(((SVOP*)first)->op_sv))) { op_free(first); *firstp = Nullop; + other->op_private |= OPpCONST_SHORTCIRCUIT; return other; } else { op_free(other); *otherp = Nullop; + first->op_private |= OPpCONST_SHORTCIRCUIT; return first; } } |