Adding such an attribute helps to detect errors in the format string at
build time. After doing this, the compiler complains about some issues:

    arch/x86/tools/relocs.c:460:5: error: format specifies type 'int'
    but the argument has type 'Elf64_Xword' (aka 'unsigned long')
    [-Werror,-Wformat]
                                    sec->shdr.sh_size);
                                    ^~~~~~~~~~~~~~~~~
    arch/x86/tools/relocs.c:464:5: error: format specifies type 'int'
    but the argument has type 'Elf64_Off' (aka 'unsigned long')
    [-Werror,-Wformat]
                                    sec->shdr.sh_offset, strerror(errno));
                                    ^~~~~~~~~~~~~~~~~~~

When relocs.c is included by relocs_32.c, sec->shdr.sh_size and
sec->shdr.sh_offset are 32-bit unsigned integers. When the file is
included by relocs_64.c, these expressions are 64-bit unsigned integers.

Add casts to unsigned long long, which length is always 64-bit, and use
%llu to format sec->shdr.sh_size and sec->shdr.sh_offset in relocs.c.

While at it, constify the format attribute of die().

Signed-off-by: Nicolas Iooss <[email protected]>
---
 arch/x86/tools/relocs.c        | 31 +++++++++++++++++--------------
 arch/x86/tools/relocs.h        |  3 ++-
 arch/x86/tools/relocs_common.c |  2 +-
 3 files changed, 20 insertions(+), 16 deletions(-)

diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
index 73eb7fd4aec4..3cc02065c677 100644
--- a/arch/x86/tools/relocs.c
+++ b/arch/x86/tools/relocs.c
@@ -397,8 +397,8 @@ static void read_shdrs(FILE *fp)
                    ehdr.e_shnum);
        }
        if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) {
-               die("Seek to %d failed: %s\n",
-                       ehdr.e_shoff, strerror(errno));
+               die("Seek to %llu failed: %s\n",
+                       (unsigned long long)ehdr.e_shoff, strerror(errno));
        }
        for (i = 0; i < ehdr.e_shnum; i++) {
                struct section *sec = &secs[i];
@@ -431,12 +431,13 @@ static void read_strtabs(FILE *fp)
                }
                sec->strtab = malloc(sec->shdr.sh_size);
                if (!sec->strtab) {
-                       die("malloc of %d bytes for strtab failed\n",
-                               sec->shdr.sh_size);
+                       die("malloc of %llu bytes for strtab failed\n",
+                               (unsigned long long)sec->shdr.sh_size);
                }
                if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
-                       die("Seek to %d failed: %s\n",
-                               sec->shdr.sh_offset, strerror(errno));
+                       die("Seek to %llu failed: %s\n",
+                               (unsigned long long)sec->shdr.sh_offset,
+                               strerror(errno));
                }
                if (fread(sec->strtab, 1, sec->shdr.sh_size, fp)
                    != sec->shdr.sh_size) {
@@ -456,12 +457,13 @@ static void read_symtabs(FILE *fp)
                }
                sec->symtab = malloc(sec->shdr.sh_size);
                if (!sec->symtab) {
-                       die("malloc of %d bytes for symtab failed\n",
-                               sec->shdr.sh_size);
+                       die("malloc of %llu bytes for symtab failed\n",
+                               (unsigned long long)sec->shdr.sh_size);
                }
                if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
-                       die("Seek to %d failed: %s\n",
-                               sec->shdr.sh_offset, strerror(errno));
+                       die("Seek to %llu failed: %s\n",
+                               (unsigned long long)sec->shdr.sh_offset,
+                               strerror(errno));
                }
                if (fread(sec->symtab, 1, sec->shdr.sh_size, fp)
                    != sec->shdr.sh_size) {
@@ -489,12 +491,13 @@ static void read_relocs(FILE *fp)
                }
                sec->reltab = malloc(sec->shdr.sh_size);
                if (!sec->reltab) {
-                       die("malloc of %d bytes for relocs failed\n",
-                               sec->shdr.sh_size);
+                       die("malloc of %llu bytes for relocs failed\n",
+                               (unsigned long long)sec->shdr.sh_size);
                }
                if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
-                       die("Seek to %d failed: %s\n",
-                               sec->shdr.sh_offset, strerror(errno));
+                       die("Seek to %llu failed: %s\n",
+                               (unsigned long long)sec->shdr.sh_offset,
+                               strerror(errno));
                }
                if (fread(sec->reltab, 1, sec->shdr.sh_size, fp)
                    != sec->shdr.sh_size) {
diff --git a/arch/x86/tools/relocs.h b/arch/x86/tools/relocs.h
index 1d23bf953a4a..f41416c31608 100644
--- a/arch/x86/tools/relocs.h
+++ b/arch/x86/tools/relocs.h
@@ -16,7 +16,8 @@
 #include <regex.h>
 #include <tools/le_byteshift.h>
 
-void die(char *fmt, ...) __attribute__((noreturn));
+void die(const char *fmt, ...) __attribute__((noreturn))
+       __attribute__((format(printf, 1, 2)));
 
 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 
diff --git a/arch/x86/tools/relocs_common.c b/arch/x86/tools/relocs_common.c
index acab636bcb34..30adb44eff79 100644
--- a/arch/x86/tools/relocs_common.c
+++ b/arch/x86/tools/relocs_common.c
@@ -1,6 +1,6 @@
 #include "relocs.h"
 
-void die(char *fmt, ...)
+void die(const char *fmt, ...)
 {
        va_list ap;
        va_start(ap, fmt);
-- 
2.11.1

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