https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90036
Bug ID: 90036
Summary: False positive: directive argument is null
[-Werror=format-overflow=]
Product: gcc
Version: 8.3.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: dilyan.palauzov at aegee dot org
Target Milestone: ---
See https://sourceware.org/bugzilla/show_bug.cgi?id=24440:
Compiling most recent binutils (git/master - commit
b05971a652c35ed72d3c95290e18) with gcc 8.3.1 20190330 fails with:
make[4]: Entering directory '/root/binutils/binutils'
gcc -DHAVE_CONFIG_H -I. -I/git/binutils-gdb/binutils -I.
-I/git/binutils-gdb/binutils -I../bfd -I/git/binutils-gdb/binutils/..
/bfd -I/git/binutils-gdb/binutils/../include
-DLOCALEDIR="\"/usr/local/share/locale\""
-Dbin_dummy_emulation=bin_vanilla_emulat
ion -W -Wall -Wstrict-prototypes -Wmissing-prototypes -Wshadow
-Wstack-usage=262144 -Werror -O2 -pipe -g -MT wrstabs.o -MD -M
P -MF .deps/wrstabs.Tpo -c -o wrstabs.o /git/binutils-gdb/binutils/wrstabs.c
/git/binutils-gdb/binutils/wrstabs.c: In function ‘stab_start_class_type’:
/git/binutils-gdb/binutils/wrstabs.c:1476:25: error: ‘%s’ directive argument is
null [-Werror=format-overflow=]
sprintf (vtable, "~%%%s", vstring);
^~
cc1: all warnings being treated as errors
make[4]: *** [Makefile:1061: wrstabs.o] Error 1
The code snippet is:
vtable = (char *) xmalloc (strlen (vstring) + 3);
sprintf (vtable, "~%%%s", vstring);
free (vstring);
Comment 1 (https://sourceware.org/bugzilla/show_bug.cgi?id=24440#c1) says:
> That doesn't make sense. vstring must be non-null since it has been passed
> to strlen already.
