Fails To Build From Source with GCC-15

[robertolumbreras]

Debian Bug report #1096847
http://bugs.debian.org/1096847

iperf3 Debian package fails to build in a test rebuild on at least amd64 with
gcc-15/g++-15, but succeeds to build with gcc-14/g++-14.

The full build log can be found at:
http://qa-logs.debian.net/2025/02/16/amd64exp/iperf3_3.18-1_unstable_gccexp.log.gz
The last lines of the build log are at the end of this report.

To build with GCC 15, either set CC=gcc-15 CXX=g++-15 explicitly,
or install the gcc, g++, gfortran, ... packages from experimental.

apt-get -t=experimental install g++

GCC 15 now defaults to the C23/C++23 standards, exposing many FTBFS.
Other Common build failures are new warnings resulting in build failures
with -Werror turned on, or new/dropped symbols in Debian symbols files.
For other C/C++ related build failures see the porting guide at
http://gcc.gnu.org/gcc-15/porting_to.html

[...]
checking that generated files are newer than configure... done
configure: creating ./config.status
config.status: creating Makefile
config.status: creating src/Makefile
config.status: creating src/version.h
config.status: creating examples/Makefile
config.status: creating iperf3.spec
config.status: creating src/iperf_config.h
config.status: executing depfiles commands
config.status: executing libtool commands
dh_auto_build
make -j8
make[1]: Entering directory '/build/reproducible-path/iperf3-3.18'
Making all in src
make[2]: Entering directory '/build/reproducible-path/iperf3-3.18/src'
make all-am
make[3]: Entering directory '/build/reproducible-path/iperf3-3.18/src'
gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c -o iperf3-main.o test -f 'main.c' || echo './'main.c
/bin/bash ../libtool --tag=CC --mode=compile gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c -o cjson.lo cjson.c
/bin/bash ../libtool --tag=CC --mode=compile gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c -o iperf_api.lo iperf_api.c
/bin/bash ../libtool --tag=CC --mode=compile gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c -o iperf_error.lo iperf_error.c
/bin/bash ../libtool --tag=CC --mode=compile gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c -o iperf_auth.lo iperf_auth.c
/bin/bash ../libtool --tag=CC --mode=compile gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c -o iperf_client_api.lo iperf_client_api.c
/bin/bash ../libtool --tag=CC --mode=compile gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c -o iperf_locale.lo iperf_locale.c
/bin/bash ../libtool --tag=CC --mode=compile gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c -o iperf_server_api.lo iperf_server_api.c
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_error.c -fPIC -DPIC -o .libs/iperf_error.o
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_client_api.c -fPIC -DPIC -o .libs/iperf_client_api.o
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_locale.c -fPIC -DPIC -o .libs/iperf_locale.o
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_api.c -fPIC -DPIC -o .libs/iperf_api.o
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_server_api.c -fPIC -DPIC -o .libs/iperf_server_api.o
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_auth.c -fPIC -DPIC -o .libs/iperf_auth.o
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c cjson.c -fPIC -DPIC -o .libs/cjson.o
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_locale.c -o iperf_locale.o >/dev/null 2>&1
/bin/bash ../libtool --tag=CC --mode=compile gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c -o iperf_tcp.lo iperf_tcp.c
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_tcp.c -fPIC -DPIC -o .libs/iperf_tcp.o
/bin/bash ../libtool --tag=CC --mode=compile gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c -o iperf_udp.lo iperf_udp.c
iperf_api.c: In function 'iperf_set_on_new_stream_callback':
iperf_api.c:608:28: error: assignment to 'void ()(struct iperf_stream )' from incompatible pointer type 'void ()(void)' [-Wincompatible-pointer-types]
608 | ipt->on_new_stream = callback;
| ^
iperf_api.c: In function 'iperf_set_on_test_start_callback':
iperf_api.c:614:28: error: assignment to 'void ()(struct iperf_test )' from incompatible pointer type 'void ()(void)' [-Wincompatible-pointer-types]
614 | ipt->on_test_start = callback;
| ^
iperf_api.c: In function 'iperf_set_on_test_connect_callback':
iperf_api.c:620:25: error: assignment to 'void ()(struct iperf_test )' from incompatible pointer type 'void ()(void)' [-Wincompatible-pointer-types]
620 | ipt->on_connect = callback;
| ^
iperf_api.c: In function 'iperf_set_on_test_finish_callback':
iperf_api.c:626:29: error: assignment to 'void ()(struct iperf_test )' from incompatible pointer type 'void ()(void)' [-Wincompatible-pointer-types]
626 | ipt->on_test_finish = callback;
| ^
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_udp.c -fPIC -DPIC -o .libs/iperf_udp.o
make[3]: *** [Makefile:971: iperf_api.lo] Error 1
make[3]: *** Waiting for unfinished jobs....
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_error.c -o iperf_error.o >/dev/null 2>&1
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_tcp.c -o iperf_tcp.o >/dev/null 2>&1
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_auth.c -o iperf_auth.o >/dev/null 2>&1
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_server_api.c -o iperf_server_api.o >/dev/null 2>&1
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_client_api.c -o iperf_client_api.o >/dev/null 2>&1
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c iperf_udp.c -o iperf_udp.o >/dev/null 2>&1
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/include -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/iperf3-3.18=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wall -pthread -c cjson.c -o cjson.o >/dev/null 2>&1
make[3]: Leaving directory '/build/reproducible-path/iperf3-3.18/src'
make[2]: *** [Makefile:733: all] Error 2
make[2]: Leaving directory '/build/reproducible-path/iperf3-3.18/src'
make[1]: *** [Makefile:404: all-recursive] Error 1
make[1]: Leaving directory '/build/reproducible-path/iperf3-3.18'
dh_auto_build: error: make -j8 returned exit code 2
make: *** [debian/rules:11: binary] Error 25
dpkg-buildpackage: error: debian/rules binary subprocess returned exit status 2

[davidBar-On]

I believe that this issue was already fixed by PR #1805 which was merged into the master branch (but is not yet in an official release).

[bmah888]

PR #1805 is still open, looking at it now.

[bmah888]

@robertolumbreras is the fix in the 3.18-2 Debian package the same as the fix in #1805 in this Github repository? If so I'm just going to merge that to the iperf3 master branch. If not, I'd like to see what's the diff between iperf 3.18 and 3.18-2 in Debian. Thanks!