-Wstringop-truncation warnings

This patch is aimed at silencing gcc8 -Wstringop-truncation warnings.

Unfortunately adding  __attribute__ ((__nonstring)) doesn't work in a
number of the places patched here, (see
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85643) so if you have
recent glibc headers installed you'll need to configure binutils with
--disable-werror to compile using gcc8 or gcc9.

include/
	* ansidecl.h: Import from gcc.
	* coff/internal.h (struct internal_scnhdr): Add ATTRIBUTE_NONSTRING
	to s_name.
	(struct internal_syment): Add ATTRIBUTE_NONSTRING to _n_name.
bfd/
	* elf-linux-core.h (struct elf_external_linux_prpsinfo32_ugid32),
	(struct elf_external_linux_prpsinfo32_ugid16),
	(struct elf_external_linux_prpsinfo64_ugid32),
	(struct elf_external_linux_prpsinfo64_ugid16): Add ATTRIBUTE_NONSTRING
	to pr_fname and pr_psargs fields.  Remove GCC diagnostic pragmas.
	Move comment to..
	* elf.c (elfcore_write_prpsinfo): ..here.  Indent nested preprocessor
	directives.
	* elf32-arm.c (elf32_arm_nabi_write_core_note): Add ATTRIBUTE_NONSTRING
	to data.
	* elf32-ppc.c (ppc_elf_write_core_note): Likewise.
	* elf32-s390.c (elf_s390_write_core_note): Likewise.
	* elf64-s390.c (elf_s390_write_core_note): Likewise.
	* elfxx-aarch64.c (_bfd_aarch64_elf_write_core_note): Likewise.
	* elf64-x86-64.c (elf_x86_64_write_core_note): Add GCC diagnostic
	pragmas.
	* peXXigen.c (_bfd_XXi_swap_scnhdr_out): Use strnlen to avoid
	false positive gcc-8 warning.
gas/
	* config/obj-evax.c (shorten_identifier): Use memcpy in place
	of strncpy.
	* config/obj-macho.c (obj_mach_o_make_or_get_sect): Ensure
	segname and sectname fields are NUL terminated.

1 files changed, 8 insertions, 31 deletions

diff --git a/bfd/elf-linux-core.h b/bfd/elf-linux-core.h
index fa0690320af..f0c4b2fc356 100644
--- a/bfd/elf-linux-core.h
+++ b/bfd/elf-linux-core.h
@@ -21,25 +21,6 @@
 #ifndef ELF_LINUX_CORE_H
 #define ELF_LINUX_CORE_H
 
-/* gcc-8 warns (*) on all the strncpy calls in this file about
-   possible string truncation.  The "truncation" is not a bug.  We
-   have an external representation of structs with fields that are not
-   necessarily NULL terminated and corresponding internal
-   representation fields that are one larger so that they can always
-   be NULL terminated.
-   gcc versions between 4.2 and 4.6 do not allow pragma control of
-   diagnostics inside functions, giving a hard error if you try to use
-   the finer control available with later versions.
-   gcc prior to 4.2 warns about diagnostic push and pop.
-   gcc-5, gcc-6 and gcc-7 warn that -Wstringop-truncation is unknown,
-   unless you also add #pragma GCC diagnostic ignored "-Wpragma".
-   (*) Depending on your system header files!  */
-
-#if GCC_VERSION >= 8000
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wstringop-truncation"
-#endif
-
 /* External 32-bit structure for PRPSINFO.  This structure is
    ABI-defined, thus we choose to use char arrays here in order to
    avoid dealing with different types in different architectures.
@@ -64,8 +45,8 @@ struct elf_external_linux_prpsinfo32_ugid32
     char pr_ppid[4];
     char pr_pgrp[4];
     char pr_sid[4];
-    char pr_fname[16];			/* Filename of executable.  */
-    char pr_psargs[80];			/* Initial part of arg list.  */
+    char pr_fname[16] ATTRIBUTE_NONSTRING;  /* Filename of executable.  */
+    char pr_psargs[80] ATTRIBUTE_NONSTRING; /* Initial part of arg list.  */
   };
 
 /* Helper function to copy an elf_internal_linux_prpsinfo in host
@@ -116,8 +97,8 @@ struct elf_external_linux_prpsinfo32_ugid16
     char pr_ppid[4];
     char pr_pgrp[4];
     char pr_sid[4];
-    char pr_fname[16];			/* Filename of executable.  */
-    char pr_psargs[80];			/* Initial part of arg list.  */
+    char pr_fname[16] ATTRIBUTE_NONSTRING;  /* Filename of executable.  */
+    char pr_psargs[80] ATTRIBUTE_NONSTRING; /* Initial part of arg list.  */
   };
 
 /* Helper function to copy an elf_internal_linux_prpsinfo in host
@@ -169,8 +150,8 @@ struct elf_external_linux_prpsinfo64_ugid32
     char pr_ppid[4];
     char pr_pgrp[4];
     char pr_sid[4];
-    char pr_fname[16];			/* Filename of executable.  */
-    char pr_psargs[80];			/* Initial part of arg list.  */
+    char pr_fname[16] ATTRIBUTE_NONSTRING;  /* Filename of executable.  */
+    char pr_psargs[80] ATTRIBUTE_NONSTRING; /* Initial part of arg list.  */
   };
 
 /* Helper function to copy an elf_internal_linux_prpsinfo in host
@@ -222,8 +203,8 @@ struct elf_external_linux_prpsinfo64_ugid16
     char pr_ppid[4];
     char pr_pgrp[4];
     char pr_sid[4];
-    char pr_fname[16];			/* Filename of executable.  */
-    char pr_psargs[80];			/* Initial part of arg list.  */
+    char pr_fname[16] ATTRIBUTE_NONSTRING;  /* Filename of executable.  */
+    char pr_psargs[80] ATTRIBUTE_NONSTRING; /* Initial part of arg list.  */
   };
 
 /* Helper function to copy an elf_internal_linux_prpsinfo in host
@@ -250,8 +231,4 @@ swap_linux_prpsinfo64_ugid16_out
   strncpy (to->pr_psargs, from->pr_psargs, sizeof (to->pr_psargs));
 }
 
-#if GCC_VERSION >= 8000
-#pragma GCC diagnostic pop
-#endif
-
 #endif