gio/gio-tool.c: In function ‘attribute_flags_to_string’:
gio/gio-tool.c:171:17: error: comparison of integer expressions of different signedness: ‘int’ and ‘long unsigned int’
171 | for (i = 0; i < G_N_ELEMENTS (flag_descr); i++)
| ^
glibc string.h declares memcpy() with attribute(nonnull(1,2)), causing
calls with NULL arguments to be treated as undefined behaviour.
This is consistent with ISO C99 and C11, which state that passing 0
to string functions as an array length does not remove the requirement
that the pointer to the array is a valid pointer.
gcc -fsanitize=undefined catches this while running OSTree's test suite.
Similarly, running the GLib test suite reports similar issues for
qsort(), memmove(), memcmp().
Signed-off-by: Simon McVittie <smcv@debian.org>
Bug: https://bugzilla.gnome.org/show_bug.cgi?id=775510
Reviewed-by: Colin Walters
