Bug#966348: ortp: FTBFS error: '__builtin_strncpy' specified bound 4 equals destination size

[Andreas Beckmann]

Source: ortp
Version: 1:1.0.2-1.1
Severity: serious
Tags: ftbfs
Justification: fails to build from source (but built successfully in the past)
Control: found -1 1:4.3.2-1

[ 24%] Building C object src/CMakeFiles/ortp.dir/rtcp.c.o
cd /build/ortp-1.0.2/obj-x86_64-linux-gnu/src && /usr/bin/cc -DBCTBX_STATIC -DHAVE_CONFIG_H -DORTP_EXPORTS -DORTP_STATIC -Dortp_EXPORTS -I/build/ortp-1.0.2/include -I/build/ortp-1.0.2/src -I/build/ortp-1.0.2/obj-x86_64-linux-gnu  -g -O2 -fdebug-prefix-map=/build/ortp-1.0.2=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -fPIC    -Wall -Wuninitialized -Werror -Wextra -Wno-unused-parameter -Wno-missing-field-initializers -fno-strict-aliasing -Wdeclaration-after-statement -Wstrict-prototypes -Wno-error=strict-prototypes -o CMakeFiles/ortp.dir/rtcp.c.o   -c /build/ortp-1.0.2/src/rtcp.c
In file included from /usr/include/string.h:495,
                 from /build/ortp-1.0.2/include/ortp/port.h:41,
                 from /build/ortp-1.0.2/include/ortp/logging.h:29,
                 from /build/ortp-1.0.2/include/ortp/ortp.h:66,
                 from /build/ortp-1.0.2/src/rtcp.c:28:
In function 'strncpy',
    inlined from 'rtcp_app_init' at /build/ortp-1.0.2/src/rtcp.c:373:2,
    inlined from 'rtp_session_send_rtcp_APP' at /build/ortp-1.0.2/src/rtcp.c:626:13:
/usr/include/x86_64-linux-gnu/bits/string_fortified.h:106:10: error: '__builtin_strncpy' specified bound 4 equals destination size [-Werror=stringop-truncation]
  106 |   return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make[3]: *** [src/CMakeFiles/ortp.dir/build.make:235: src/CMakeFiles/ortp.dir/rtcp.c.o] Error 1

This is probably gcc-10 doing more checking than previous versions.


Andreas