compile error

[ThomasWaldmann]

/bin/bash ./libtool --tag=CC   --mode=compile gcc -DHAVE_CONFIG_H -I. -I. -I. -I./../include  -DHAVE_x86_64_elf64_vec -DHAVE_i386_elf32_vec -DHAVE_iamcu_elf32_vec -DHAVE_x86_64_elf32_vec -DHAVE_i386_aout_linux_vec -DHAVE_i386_pei_vec -DHAVE_x86_64_pei_vec -DHAVE_l1om_elf64_vec -DHAVE_k1om_elf64_vec -DHAVE_elf64_le_vec -DHAVE_elf64_be_vec -DHAVE_elf32_le_vec -DHAVE_elf32_be_vec -DHAVE_plugin_vec  -DBINDIR='"/usr/local/bin"'  -W -Wall -Wstrict-prototypes -Wmissing-prototypes -Wshadow -Wstack-usage=262144 -Werror -I./../zlib -g -O2 -MT pei-i386.lo -MD -MP -MF .deps/pei-i386.Tpo -c -o pei-i386.lo pei-i386.c
libtool: compile:  gcc -DHAVE_CONFIG_H -I. -I. -I. -I./../include -DHAVE_x86_64_elf64_vec -DHAVE_i386_elf32_vec -DHAVE_iamcu_elf32_vec -DHAVE_x86_64_elf32_vec -DHAVE_i386_aout_linux_vec -DHAVE_i386_pei_vec -DHAVE_x86_64_pei_vec -DHAVE_l1om_elf64_vec -DHAVE_k1om_elf64_vec -DHAVE_elf64_le_vec -DHAVE_elf64_be_vec -DHAVE_elf32_le_vec -DHAVE_elf32_be_vec -DHAVE_plugin_vec -DBINDIR=\"/usr/local/bin\" -W -Wall -Wstrict-prototypes -Wmissing-prototypes -Wshadow -Wstack-usage=262144 -Werror -I./../zlib -g -O2 -MT pei-i386.lo -MD -MP -MF .deps/pei-i386.Tpo -c pei-i386.c -o pei-i386.o

In file included from coff-i386.c:614:0,
                 from pei-i386.c:45:
coffcode.h: In function ‘coff_write_object_contents’:
coffcode.h:3775:46: error: ‘%lu’ directive output may be truncated writing between 1 and 20 bytes into a region of size 8 [-Werror=format-truncation=]
        snprintf (s_name_buf, SCNNMLEN + 1, "/%lu", (unsigned long) string_size);
                                              ^~~
coffcode.h:3775:44: note: directive argument in the range [4, 18446744073709551614]
        snprintf (s_name_buf, SCNNMLEN + 1, "/%lu", (unsigned long) string_size);
                                            ^~~~~~
In file included from /usr/include/stdio.h:862:0,
                 from sysdep.h:37,
                 from pei-i386.c:21:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:64:10: note: ‘__builtin___snprintf_chk’ output between 3 and 22 bytes into a destination of size 9
   return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        __bos (__s), __fmt, __va_arg_pack ());
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors

[ThomasWaldmann]

OS: Ubuntu Linux 18.04 amd64 (pre-release)

I tried current master and d2ae637d commit (the one you used for the offered binaries), the error happens for both.

Any ideas?

[igrr]

@ThomasWaldmann What arguments are you passing to ./configure?

[ThomasWaldmann]

None. Should I?

[fivdi]

Which version of gcc is being used for compiling? Probably gcc7, is this correct? If so, the compiler is generating the warning because string_size is being cast to an unsigned long which is potentially a 20 digit number (for example, 18446744073709551614) but s_name_buf is a 9 char buffer so gcc thinks the buffer might not be big enough.

Here's the line of code that generates the warning:

	snprintf (s_name_buf, SCNNMLEN + 1, "/%lu", (unsigned long) string_size);

s_name_buf is defined like this in this repository:

	char s_name_buf[SCNNMLEN + 1];

SCNNMLEN is defined like this:

#define SCNNMLEN (8)

As can be seen here, a more up-to-date version of binutils has a fix for the issue:

               /* The s_name field is defined to be NUL-padded but need not be
                  NUL-terminated.  We use a temporary buffer so that we can still
                  sprintf all eight chars without splatting a terminating NUL
                  over the first byte of the following member (s_paddr).  */
               /* PR 21096: The +20 is to stop a bogus warning from gcc7 about
                  a possible buffer overflow.  */
               char s_name_buf[SCNNMLEN + 1 + 20];

@ThomasWaldmann I'd suggest passing the parameters shown here to ./configure unless you have a reason to do otherwise.

[ThomasWaldmann]

gcc version 7.3.0 (Ubuntu 7.3.0-11ubuntu1)

[Lapshin]

Closing as outdated.

The project is moved to https://github.com/espressif/binutils-gdb repo (branch name pattern esp32ulp-elf-*). Create issue in the new project if found something