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[RFA] Fix type_stack leaks in c expression parsing.
- From: Philippe Waroquiers <philippe dot waroquiers at skynet dot be>
- To: gdb-patches at sourceware dot org
- Cc: Philippe Waroquiers <philippe dot waroquiers at skynet dot be>
- Date: Sat, 9 Feb 2019 20:50:00 +0100
- Subject: [RFA] Fix type_stack leaks in c expression parsing.
Valgrind detects a bunch of leaks in several tests, such as:
==22905== 40 (24 direct, 16 indirect) bytes in 1 blocks are definitely lost in loss record 531 of 3,268
==22905== at 0x4C2C4CC: operator new(unsigned long) (vg_replace_malloc.c:344)
==22905== by 0x5893AD: get_type_stack() (parse.c:1509)
==22905== by 0x3F4EAD: c_yyparse() (c-exp.y:1223)
==22905== by 0x3F71BC: c_parse(parser_state*) (c-exp.y:3308)
==22905== by 0x588CEA: parse_exp_in_context_1(char const**, unsigned long, block const*, int, int, int*) [clone .constprop.89] (parse.c:1205)
==22905== by 0x588FA1: parse_exp_in_context (parse.c:1108)
==22905== by 0x588FA1: parse_exp_1 (parse.c:1099)
==22905== by 0x588FA1: parse_expression(char const*) (parse.c:1247)
...
==22395== 456 (168 direct, 288 indirect) bytes in 7 blocks are definitely lost in loss record 2,658 of 2,978
==22395== at 0x4C2C4CC: operator new(unsigned long) (vg_replace_malloc.c:344)
==22395== by 0x5893AD: get_type_stack() (parse.c:1509)
==22395== by 0x3F4ECF: c_yyparse() (c-exp.y:1230)
==22395== by 0x3F71BC: c_parse(parser_state*) (c-exp.y:3308)
==22395== by 0x588CEA: parse_exp_in_context_1(char const**, unsigned long, block const*, int, int, int*) [clone .constprop.89] (parse.c:1205)
==22395== by 0x588FA1: parse_exp_in_context (parse.c:1108)
==22395== by 0x588FA1: parse_exp_1 (parse.c:1099)
==22395== by 0x588FA1: parse_expression(char const*) (parse.c:1247)
==22395== by 0x67BB9D: whatis_exp(char const*, int) (typeprint.c:515)
...
==22395== VALGRIND_GDB_ERROR_BEGIN
==22395== 144 (24 direct, 120 indirect) bytes in 1 blocks are definitely lost in loss record 1,016 of 2,978
==22395== at 0x4C2C4CC: operator new(unsigned long) (vg_replace_malloc.c:344)
==22395== by 0x5893AD: get_type_stack() (parse.c:1509)
==22395== by 0x3F4E8A: c_yyparse() (c-exp.y:1217)
==22395== by 0x3F71BC: c_parse(parser_state*) (c-exp.y:3308)
==22395== by 0x588CEA: parse_exp_in_context_1(char const**, unsigned long, block const*, int, int, int*) [clone .constprop.89] (parse.c:1205)
==22395== by 0x588FA1: parse_exp_in_context (parse.c:1108)
==22395== by 0x588FA1: parse_exp_1 (parse.c:1099)
==22395== by 0x588FA1: parse_expression(char const*) (parse.c:1247)
==22395== by 0x67BB9D: whatis_exp(char const*, int) (typeprint.c:515)
...
Fix these by storing the allocated type_stack in the cpstate->type_stacks
vector.
Tested on debian/amd64, natively and under valgrind.
gdb/ChangeLog
2019-02-09 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* c-exp.y (direct_abs_decl): emplace_back type_stack.
---
gdb/c-exp.y | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/gdb/c-exp.y b/gdb/c-exp.y
index f3ef23c75a..508e9ef28d 100644
--- a/gdb/c-exp.y
+++ b/gdb/c-exp.y
@@ -1215,12 +1215,14 @@ direct_abs_decl: '(' abs_decl ')'
push_type_int ($2);
push_type (tp_array);
$$ = get_type_stack ();
+ cpstate->type_stacks.emplace_back ($$);
}
| array_mod
{
push_type_int ($1);
push_type (tp_array);
$$ = get_type_stack ();
+ cpstate->type_stacks.emplace_back ($$);
}
| direct_abs_decl func_mod
@@ -1228,11 +1230,13 @@ direct_abs_decl: '(' abs_decl ')'
push_type_stack ($1);
push_typelist ($2);
$$ = get_type_stack ();
+ cpstate->type_stacks.emplace_back ($$);
}
| func_mod
{
push_typelist ($1);
$$ = get_type_stack ();
+ cpstate->type_stacks.emplace_back ($$);
}
;
--
2.20.1