Cannot build 1.5.1

[merdely]

Hi

I'm trying to build 1.5.1 on Arch Linux and I'm getting this in my output:

make[1]: Entering directory '/tmp/naemon-naemon-core-611a5b6'
  CC       src/naemon/naemon-naemon.o
  CC       src/naemon/broker.lo
  CC       src/naemon/checks.lo
src/naemon/checks.c: In function 'parse_output':
src/naemon/checks.c:114:19: error: assignment discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
  114 |                 p = strpbrk((const char *) tmp, "|");
      |                   ^
src/naemon/checks.c:141:19: error: assignment discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
  141 |                 p = strpbrk((const char *) tmp, "|");
      |                   ^
cc1: all warnings being treated as errors
make[1]: *** [Makefile:2009: src/naemon/checks.lo] Error 1
make[1]: Leaving directory '/tmp/naemon-naemon-core-611a5b6'
make: *** [Makefile:1355: all] Error 2

I'm not sure of the RIGHT way to fix it. I was able to get the warnings to go away if I do this:

p = strpbrk(tmp, "|");

But there are more instances of this structure throughout the code and I'm not even sure if this is right.

bang = (char *)strchr(name, '!');

Help, please

[nook24]

It looks like this issue is related to #522, and I was able to reproduce this on my side as well.

[root@a8a35a7d2a79 naemon-core-1.5.1]# lsb_release -a
LSB Version:	n/a
Distributor ID:	Arch
Description:	Arch Linux
Release:	rolling
Codename:	n/a

[root@a8a35a7d2a79 naemon-core-1.5.1]# gcc --version
gcc (GCC) 15.2.1 20260209
Copyright (C) 2025 Free Software Foundation, Inc.

It's interesting that it is failing now, even if the GCC version claims to be the same as I was successfully able to build it in this comment: #522 (comment) a few weeks ago.

What ever. From my understanding of the error

src/naemon/checks.c:114:19: error: assignment discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
  114 |                 p = strpbrk((const char *) tmp, "|");
      |                   ^

it looks like strpbrk is returning a const char *, because the input was also a const char *. Since we are not writing to p anyway we could define it as const char *p;.
How ever, this would require a change of

tmp = strtok_r(p + 1, "\n", &saveptr);

to be

tmp = strtok_r((char *)(p + 1), "\n", &saveptr);

as strtok_r expects a writable variable.

I would recommend to cast the result of strpbrk to a char * like so:

p = (char *) strpbrk((const char *) tmp, "|");

From my understanding, the whole const char * is some compiler magic as the man page claims that the function returns a char *: https://man.archlinux.org/man/strpbrk.3 C++ has an overloaded version which can return both, a char * and a const char * based on the input value: https://cplusplus.com/reference/cstring/strpbrk/
This also claims that in C no overloaded version is available, but the error doesn't lie I guess :)

---

I think that your approach to pass in a char *

p = strpbrk(tmp, "|");

is based on exactly that compiler magic and could lead to issues with older GCC versions because the input of strpbrk is expected to be a const char *.

[nook24]

I have created a Patch to resolve this. Would be good if you could give it a shot: #531