When compiling xdebug by LLVM (for example on FreeBSD-head), compilers produce this warning:

...
cc -I. -I/usr/home/oleg/php-xdebug/work/xdebug-2.2.3 -DPHP_ATOM_INC -I/usr/home/oleg/php-xdebug/work/xdebug-2.2.3/include -I/usr/home/oleg/php-xdebug/work/xdebug-2.2.3/main -I/usr/home/oleg/php-xdebug/work/xdebug-2.2.3 -I/usr/local/include/php -I/usr/local/include/php/main -I/usr/local/include/php/TSRM -I/usr/local/include/php/Zend -I/usr/local/include/php/ext -I/usr/local/include/php/ext/date/lib -DHAVE_CONFIG_H -O2 -pipe -fno-strict-aliasing -c /usr/home/oleg/php-xdebug/work/xdebug-2.2.3/xdebug_handler_dbgp.c -fPIC -DPIC -o .libs/xdebug_handler_dbgp.o
/usr/home/oleg/php-xdebug/work/xdebug-2.2.3/xdebug_handler_dbgp.c:1310:21: warning: incompatible pointer types initializing 'jmp_buf ' (aka 'struct _jmp_buf ()[1]') with an expression of type 'sigjmp_buf ' (aka 'struct _sigjmp_buf ()[1]')
[-Wincompatible-pointer-types]
jmp_buf original_bailout = EG(bailout);
^ ~~~
/usr/home/oleg/php-xdebug/work/xdebug-2.2.3/xdebug_handler_dbgp.c:1345:14: warning: incompatible pointer types assigning to 'sigjmp_buf ' (aka 'struct _sigjmp_buf ()[1]') from 'jmp_buf ' (aka 'struct _jmp_buf ()[1]') [-Wincompatible-pointer-types]
EG(bailout) = original_bailout;
^ ~~~~
/usr/home/oleg/php-xdebug/work/xdebug-2.2.3/xdebug_handler_dbgp.c:2003:28: warning: passing 'const char ' to parameter of type 'char ' discards qualifiers [-Wincompatible-pointer-types-discards-qualifiers]
xdebug_hash_add(tmp_hash, hash_key->arKey, strlen(hash_key->arKey), hash_key->arKey);
^~~~~~~
./xdebug_hash.h:75:74: note: expanded from macro 'xdebug_hash_add'
#define xdebug_hash_add(h, key, key_len, p) xdebug_hash_add_or_update(h, key, key_len, 0, p)
^
./xdebug_hash.h:66:54: note: passing argument to parameter 'str_key' here
int xdebug_hash_add_or_update(xdebug_hash h, char str_key, unsigned int str_key_len, unsigned long num_key, const void p);
^
3 warnings generated.
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