When we open debug mode(`./configure --devel`),
GCC will check `sign-conversion` and `conversion`.
It will cause some warnings.
Also add `-DDEBUG` to `CFLAGS` if we open debug
mode. This can open `PDEBUG()` and help you to get
detail information.
Signed-off-by: Jack Hu <spcreply@126.com>
Previously, the value of it was kept from the loop over all the command-line arguments; as `/usr/lib` or `/lib` were far enough in the list, on many systems there was no difference, but `own_dir` and `LIB_DIR` could be ignored or not based on the argument count, which was confusing.
Recent GCC added checks for this and it triggers `Werror` with
```
In function 'strncpy',
inlined from 'proxy_gethostbyname' at src/core.c:832:2:
/nix/store/hayaj8q9rc7swx4llcjqymmg3zr525lx-glibc-2.32-25-dev/include/bits/string_fortified.h:91:10: error: '__builtin_strncpy' specified bound 8192 equals destination size [8;;https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wstringop-truncation-Werror=stringop-truncation8;;]
91 | return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function 'strncpy',
inlined from 'proxy_getaddrinfo' at src/core.c:917:3:
/nix/store/hayaj8q9rc7swx4llcjqymmg3zr525lx-glibc-2.32-25-dev/include/bits/string_fortified.h:91:10: error: '__builtin_strncpy' specified bound 256 equals destination size [8;;https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wstringop-truncation-Werror=stringop-truncation8;;]
91 | return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
```
Implements support for an environmnet variable (PROXY_DNS_SERVER) whereby
the user can specify a DNS server. If not set defaults to the hardcoded
OpenDNS default.
When inlining check_path(), gcc sees after the first snprintf()
call that pbuf might be null, and subsequently generates a warning
for the next snprintf() call. Since the code (erroneously) builds
with -Werror, this causes it to fail.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83139
