https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97350
--- Comment #10 from Jan Hubicka <hubicka at gcc dot gnu.org> ---
OK, I was poking a bit about the problem and indeed the bootstrapped gnat with
-O3 and PGO ices, while gnat built normally does not.
We fail:
#2 0x00000000019b7dcb in _Z13variable_sizeP9tree_node (size=0x7ffff7448900) at
../../gcc/stor-layout.c:172
172 gcc_assert (self_refs.length () > 0);
(gdb) l
167 if (TREE_CODE (t) == CALL_EXPR || self_referential_component_ref_p
(t))
168 return size;
169
170 /* Collect the list of self-references in the expression. */
171 find_placeholder_in_expr (size, &self_refs);
172 gcc_assert (self_refs.length () > 0);
173
174 /* Obtain a private copy of the expression. */
175 t = size;
here the gcc_assert fires. Sadly self_refs has no debug info.
Size is:
<cond_expr 0x7ffff7448900
type <integer_type 0x7ffff745f0a8 bitsizetype public unsigned TI
size <integer_cst 0x7ffff744ac00 constant visited 128>
unit-size <integer_cst 0x7ffff744ac18 constant visited 16>
align:128 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x7ffff745f0a8 precision:128 min <integer_cst 0x7ffff744ac30 0> max
<integer_cst 0x7ffff745e848 0xffffffffffffffffffffffffffffffff>>
readonly
arg:0 <ge_expr 0x7ffff7470640
type <boolean_type 0x7ffff746ae70 boolean sizes-gimplified public
visited unsigned QI
size <integer_cst 0x7ffff744aca8 constant visited 8>
unit-size <integer_cst 0x7ffff744acc0 constant visited 1>
align:8 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x7ffff746ae70 precision:8 min <integer_cst 0x7ffff74680d8 0> max <integer_cst
0x7ffff7468000 255> context <translation_unit_decl 0x7ffff7454168 a-assert.adb>
RM size <integer_cst 0x7ffff744afa8 1> RM max <integer_cst 0x7ffff7468108 1>>
readonly visited
arg:0 <component_ref 0x7ffff74487e0 type <integer_type 0x7ffff746c1f8
positive___XDLU_1__2147483647>
readonly visited
arg:0 <indirect_ref 0x7ffff744b7c0 type <record_type 0x7ffff746cc78
string___XUB>
readonly nothrow visited
arg:0 <component_ref 0x7ffff7448750 type <pointer_type
0x7ffff746cd20>
visited
arg:0 <placeholder_expr 0x7ffff7468510 type <record_type
0x7ffff746cf18 string___XUP>
visited> arg:1 <field_decl 0x7ffff7467a18 P_BOUNDS>>>
arg:1 <field_decl 0x7ffff7473260 UB0>>
arg:1 <component_ref 0x7ffff74487b0 type <integer_type 0x7ffff746c1f8
positive___XDLU_1__2147483647>
readonly visited arg:0 <indirect_ref 0x7ffff744b7c0> arg:1
<field_decl 0x7ffff74731c8 LB0>>>
arg:1 <mult_expr 0x7ffff74706e0 type <integer_type 0x7ffff745f0a8
bitsizetype>
readonly
arg:0 <nop_expr 0x7ffff744b8c0 type <integer_type 0x7ffff745f0a8
bitsizetype>
readonly
arg:0 <plus_expr 0x7ffff74706b8 type <integer_type 0x7ffff745f000
sizetype>
readonly
arg:0 <minus_expr 0x7ffff7470690 type <integer_type
0x7ffff745f000 sizetype>
readonly
arg:0 <nop_expr 0x7ffff744b840 type <integer_type
0x7ffff745f000 sizetype>
readonly visited arg:0 <component_ref 0x7ffff74487e0>>
arg:1 <nop_expr 0x7ffff744b820 type <integer_type
0x7ffff745f000 sizetype>
readonly visited arg:0 <component_ref 0x7ffff74487b0>>>
arg:1 <integer_cst 0x7ffff744acc0 1>>> arg:1 <integer_cst 0x7ffff744aca8 8>>
arg:2 <integer_cst 0x7ffff744ac30 type <integer_type 0x7ffff745f0a8
bitsizetype> constant 0>>
<PLACEHOLDER_EXPR struct >.P_BOUNDS->UB0 >= <PLACEHOLDER_EXPR struct
>.P_BOUNDS->LB0 ? (bitsizetype) (((sizetype) <PLACEHOLDER_EXPR struct
>.P_BOUNDS->UB0 - (sizetype) <PLACEHOLDER_EXPR struct >.P_BOUNDS->LB0) + 1) * 8
: 0;
I am not expert on Ada type sizes but it seems like well formed expression.
and backtrace is:
#0 _Z14internal_errorPKcz (gmsgid=0xac <error: Cannot access memory at address
0xac>) at ../../gcc/diagnostic.c:1752
#1 0x00000000010ba114 in _Z11fancy_abortPKciS0_ (file=0x23a38a8 "in %s, at
%s:%d", line=172, function=0x1e507bb "self_referential_size") at
../../gcc/diagnostic.c:1824
#2 0x00000000019b7dcb in _Z13variable_sizeP9tree_node (size=0x7ffff7448900) at
../../gcc/stor-layout.c:172
#3 _Z13variable_sizeP9tree_node (size=0x7ffff7448900) at
../../gcc/stor-layout.c:67
#4 0x000000000128f4e0 in finalize_type_size (type=0x7ffff746c3f0) at
../../gcc/stor-layout.c:1967
#5 0x000000000128df40 in _Z11layout_typeP9tree_node (type=0x23a38a8) at
../../gcc/stor-layout.c:2625
#6 0x000000000190e307 in _ZL18build_array_type_1P9tree_nodeS0_bbb.lto_priv.0
(elt_type=0x7ffff745f3f0, index_type=0x7ffff746c348, typeless_storage=59,
shared=172, set_canonical=59)
at ../../gcc/tree.c:8194
#7 0x0000000001567bcc in _Z18gnat_to_gnu_entityiP9tree_nodeb
(gnat_entity=37370024, gnu_expr=0x1e507bb, definition=59) at
../../gcc/ada/gcc-interface/decl.c:2366
#8 0x00000000015618f5 in _Z16gnat_to_gnu_typei (gnat_entity=37370024) at
../../gcc/ada/gcc-interface/decl.c:4887
#9 0x00000000015687a9 in _Z18gnat_to_gnu_entityiP9tree_nodeb
(gnat_entity=37370024, gnu_expr=0x1e507bb, definition=59) at
../../gcc/ada/gcc-interface/decl.c:4814
#10 0x00000000015618f5 in _Z16gnat_to_gnu_typei (gnat_entity=37370024) at
../../gcc/ada/gcc-interface/decl.c:4887
#11 0x00000000019ea47c in gigi (gnat_root=37370024, max_gnat_node=31786939,
number_name=30016059, nodes_ptr=0xac, flags_ptr=0x1ca023b, next_node_ptr=0x73,
prev_node_ptr=0x0,
elists_ptr=0x0, elmts_ptr=0x0, strings_ptr=0x0, string_chars_ptr=0x0,
list_headers_ptr=0x0, number_file=12, file_info_ptr=0x7fffffffe3c0,
standard_boolean=16, standard_integer=37,
standard_character=107, standard_long_long_float=100,
standard_exception_type=1704, gigi_operating_mode=0) at
../../gcc/ada/gcc-interface/trans.c:463
#12 0x00000000019e406d in back_end__call_back_end (mode=(unknown: 1704)) at
../../gcc/ada/back_end.adb:155
#13 0x0000000001928eed in _ada_gnat1drv () at ../../gcc/ada/gnat1drv.adb:1608
#14 0x0000000001910a4b in _ZL15gnat_parse_filev.lto_priv.0 () at
../../gcc/ada/gcc-interface/misc.c:118
#15 0x00000000019107f4 in _ZL12compile_filev.lto_priv.0 () at
../../gcc/toplev.c:460
#16 0x00000000018f3296 in _ZN6toplev4mainEiPPc (this=0x7fffffffe63e, argc=21,
argv=0x7fffffffe728) at ../../gcc/toplev.c:2321
#17 0x00000000018f26ec in main (argc=30016059, argv=0x1ca023b) at
../../gcc/main.c:39
Breakpointing on 171 works and vector seems to be filled in. However the
disasembly shows:
0x00000000019b7db2 <+98>: callq 0x1a1c050
<_Z24find_placeholder_in_exprP9tree_nodeP3vecIS0_7va_heap6vl_ptrE>
=> 0x00000000019b7db7 <+103>: mov $0x1e507bb,%edx
0x00000000019b7dbc <+108>: mov $0xac,%esi
0x00000000019b7dc1 <+113>: mov $0x1ca0231,%edi
0x00000000019b7dc6 <+118>: callq 0x10ba0f0 <_Z11fancy_abortPKciS0_>
so it seems that the vector length test is completely optimized out in function
_Z13variable_sizeP9tree_node (after call to
_Z24find_placeholder_in_exprP9tree_nodeP3vecIS0_7va_heap6vl_ptrE).
