Hi Ervin, > Le 30 août 2020 à 11:44, Ervin Hegedüs <airw...@gmail.com> a écrit : > > Hi all, > > and in parser: > > https://github.com/airween/flextest/blob/master/myparser.y#L52 > > config_directive_line: > T_CONFIG_DIRECTIVE T_CONFIG_DIRECTIVE_ARGUMENT { printf("'%s' '%s'\n", > $1, $2); free($1); free($2); } > > This works as well, but I found some interesting thing when I > analyzed my code with valgrind: the pushed token is still > reachable when the parser run into an error. > > There is a wrong config: badconf.conf. > > Here is the result: > > valgrind -s --leak-check=full --show-leak-kinds=all --track-origins=yes > ./myparser badconf.conf > > ==564114== 4 bytes in 1 blocks are still reachable in loss record 1 of 4 > ==564114== at 0x483677F: malloc (in > /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so) > ==564114== by 0x48EB71A: strdup (strdup.c:42) > ==564114== by 0x10B86A: push_sym (mylexer.l:111) > ==564114== by 0x109E7F: yylex (mylexer.l:53) > ==564114== by 0x10954B: yyparse (myparser.tab.c:1055) > ==564114== by 0x10BD38: open_and_parse (mylexer.l:221) > ==564114== by 0x10BF98: main (mylexer.l:272) > > > How can I avoid this situation? Is that any "best-practice"? How > can I access to pointers in stack to free them when error > occurred?
I have not read all in details, but I believe you need to read about %destructor. https://www.gnu.org/software/bison/manual/html_node/Destructor-Decl.html Cheers!
