fluent
fluent-bit 3.0.3+ fails to build with -Wincompatible-pointer-types and -Wpointer-sign
Bug Report
Describe the bug
When building the fluent-bit AUR package for versions 3.0.3 or 3.0.4 on Archlinux, the build fails with these errors:
/build/fluent-bit/src/src/tls/openssl.c:220:40: error: passing argument 1 of ‘SSL_select_next_proto’ from incompatible pointer type [-Wincompatible-pointer-types]
/usr/include/openssl/ssl.h:828:50: note: expected ‘unsigned char **’ but argument is of type ‘const unsigned char **’
/build/fluent-bit/src/src/tls/openssl.c:222:40: warning: pointer targets in passing argument 3 of ‘SSL_select_next_proto’ differ in signedness [-Wpointer-sign]
/usr/include/openssl/ssl.h:829:55: note: expected ‘const unsigned char *’ but argument is of type ‘char *’
This is code introduced in commits 1feb741e8fcf1667b6c7dcc47da314fa7679b601 and 5340b4c1247615637281c14236be0eb9002d1569.
Is the intention to be able to build with -Wincompatible-pointer-types and -Wpointer-sign, or should I relax the build options for the fluent-bit AUR package?
To Reproduce
- Clone the fluent-bit AUR package
- Build on Archlinux with
extra-x86_64-build
Your Environment
- Version used: 3.0.3, 3.0.4
- Configuration: -
- Environment name and version (e.g. Kubernetes? What version?): -
- Server type and version: -
- Operating System and version: Archlinux, with openssl 3.3.0-1
- Filters and plugins: -
Additional context
N/A
Update:
After patching the code to prevent the warnings, the build fails on other warnings, a -Wformat in plugins/kubernetes_events/kubernetes_events.c.
I can't build 3.0.2 either, this used to work before, but in the log file of an earlier build of 3.0.2, the -Wincompatible-pointer-types and -Wpointer-sign warnings were already there, without failing the build. Something must have changed in Archlinux itself.
I'll keep investigating...
@j0057 could this be due to an upgrade of GCC to 14.1? https://gcc.gnu.org/gcc-14/porting_to.html#warnings-as-errors
Type checking on pointer types (-Werror=incompatible-pointer-types)
GCC no longer allows implicitly casting all pointer types to all other pointer types. This behavior is now restricted to the void * type and its qualified variations.
I checked with 13.2 and the program still compiles, from 14.1 this warning is now an error so compilation fails.
I've made a PR here that might be able to fix it: https://github.com/fluent/fluent-bit/pull/8901. If nothing else you could probably turn that into a patch for the package to fix it until it's sorted out upstream.
