https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70804
Bug ID: 70804
Summary: Missed tail-call
Product: gcc
Version: 6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: ramana at gcc dot gnu.org
Target Milestone: ---
Given.
struct E {
virtual ~E() { destroy(); }
virtual E *clone() = 0;
void destroy();
};
struct B: public E {
virtual ~B() {}
virtual B *clone() { return 0; }
virtual void bar() {}
};
void f(void) { B b; }
Notice the missing tail call to E:destroy from f.
.file "m.cpp"
.section
.text._ZN1B5cloneEv,"axG",%progbits,_ZN1B5cloneEv,comdat
.align 2
.p2align 3,,7
.weak _ZN1B5cloneEv
.type _ZN1B5cloneEv, %function
_ZN1B5cloneEv:
.LFB8:
.cfi_startproc
mov x0, 0
ret
.cfi_endproc
.LFE8:
.size _ZN1B5cloneEv, .-_ZN1B5cloneEv
.section .text._ZN1B3barEv,"axG",%progbits,_ZN1B3barEv,comdat
.align 2
.p2align 3,,7
.weak _ZN1B3barEv
.type _ZN1B3barEv, %function
_ZN1B3barEv:
.LFB9:
.cfi_startproc
ret
.cfi_endproc
.LFE9:
.size _ZN1B3barEv, .-_ZN1B3barEv
.section .text._ZN1BD2Ev,"axG",%progbits,_ZN1BD5Ev,comdat
.align 2
.p2align 3,,7
.weak _ZN1BD2Ev
.type _ZN1BD2Ev, %function
_ZN1BD2Ev:
.LFB5:
.cfi_startproc
ldr x1, .LC0
str x1, [x0]
b _ZN1E7destroyEv
.cfi_endproc
.LFE5:
.size _ZN1BD2Ev, .-_ZN1BD2Ev
.align 3
.LC0:
.xword _ZTV1E+16
.weak _ZN1BD1Ev
_ZN1BD1Ev = _ZN1BD2Ev
.section .text._ZN1BD0Ev,"axG",%progbits,_ZN1BD5Ev,comdat
.align 2
.p2align 3,,7
.weak _ZN1BD0Ev
.type _ZN1BD0Ev, %function
_ZN1BD0Ev:
.LFB7:
.cfi_startproc
stp x19, x30, [sp, -16]!
.cfi_def_cfa_offset 16
.cfi_offset 19, -16
.cfi_offset 30, -8
ldr x1, .LC1
mov x19, x0
str x1, [x0]
bl _ZN1E7destroyEv
mov x0, x19
ldp x19, x30, [sp], 16
.cfi_restore 30
.cfi_restore 19
.cfi_def_cfa_offset 0
b _ZdlPv
.cfi_endproc
.LFE7:
.size _ZN1BD0Ev, .-_ZN1BD0Ev
.align 3
.LC1:
.xword _ZTV1E+16
.text
.align 2
.p2align 3,,7
.global _Z1fv
.type _Z1fv, %function
_Z1fv:
.LFB10:
.cfi_startproc
str x30, [sp, -32]!
.cfi_def_cfa_offset 32
.cfi_offset 30, -32
ldr x1, .LC2
add x0, sp, 32
str x1, [x0, -8]!
bl _ZN1E7destroyEv
ldr x30, [sp], 32
.cfi_restore 30
.cfi_def_cfa_offset 0
ret
.cfi_endproc
.LFE10:
.size _Z1fv, .-_Z1fv
.align 3
.LC2:
.xword _ZTV1E+16
.weak _ZTS1E
.section .rodata._ZTS1E,"aG",%progbits,_ZTS1E,comdat
.align 3
.type _ZTS1E, %object
.size _ZTS1E, 3
_ZTS1E:
.string "1E"
.weak _ZTI1E
.section .rodata._ZTI1E,"aG",%progbits,_ZTI1E,comdat
.align 3
.type _ZTI1E, %object
.size _ZTI1E, 16
_ZTI1E:
.xword _ZTVN10__cxxabiv117__class_type_infoE+16
.xword _ZTS1E
.weak _ZTV1E
.section .rodata._ZTV1E,"aG",%progbits,_ZTV1E,comdat
.align 3
.type _ZTV1E, %object
.size _ZTV1E, 40
_ZTV1E:
.xword 0
.xword _ZTI1E
.xword 0
.xword 0
.xword __cxa_pure_virtual
