kconfig: Don't leak symbol names during parsing
Prior to this fix, zconf.y did not free symbol names from zconf.l in
these contexts:
- After T_CONFIG ('config LEAKED')
- After T_MENUCONFIG ('menuconfig LEAKED')
- After T_SELECT ('select LEAKED')
- After T_IMPLY ('imply LEAKED')
- After T_DEFAULT in a choice ('default LEAKED')
All of these come in the form of T_WORD tokens, which always have their
associated string allocated on the heap in zconf.l and need to be freed.
Fix by introducing a new nonterminal 'nonconst_symbol' which takes a
T_WORD, fetches the symbol, and then frees the T_WORD string. The
already existing 'symbol' nonterminal works the same way but also
accepts T_WORD_QUOTE, corresponding to a constant symbol. T_WORD_QUOTE
should not be accepted in any of the contexts above, so the 'symbol'
nonterminal can't be reused here.
Fetching the symbol in 'nonconst_symbol' also removes a bunch of
sym_lookup() calls from actions.
Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:
LEAK SUMMARY:
definitely lost: 711,571 bytes in 37,756 blocks
...
Summary after the fix:
LEAK SUMMARY:
definitely lost: 387,504 bytes in 15,545 blocks
...
Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
1 file changed