[tnozaki-elftoolchain] TNF local patch for libelf - LIBELF_COPY_U32/LIBELF_COPY_S32 range check

[Takehiko NOZAKI]

No description provided.

[Takehiko NOZAKI]

original code has bug, but thorpej's fix may causes another problem…

LIBELF_COPY_U32:

if ((SRC)->NAME > UINT32_MAX) {         \

(SRC)->NAME mat take:

• Elf32_{Word,Addr,Off} - uint32_t
• Elf64_{XWord,Addr,Off} - uint64_t
  so this comparison may cause no effect when type is uint32_t.
  but gcc -Wtype-limits may not detect it unlike (SRC)->NAME < 0.
  lint(1) may cause alarm?

LIBELF_COPY_S32:

if ((SRC)->NAME > INT32_MAX ||          \
    (SRC)->NAME < INT32_MIN) {          \

(SRC)->NAME may take:

• Elf32_Word - uint32_t
• Elf32_Sword - int32_t
• Elf64_Xword - uint64_t
• Elf64_Sxword - int64_t
  consider following case:
• when (SRC)->NAME type is uint{32,64}_t, comparison x < INT32_MIN may not work correctly, apparently BUG
• when uint32_t case, cast (int64_t)(SRC)->NAME cause -Werror=type-limits problem, for N WARNS=4 in mk.conf sets -this flag…

‌

[Takehiko NOZAKI]

oops, LIBELF_COPY_S32() case:

$ grep LIBELF_COPY_S32
./dist/_libelf.h:#define        LIBELF_COPY_S32(DST,SRC,NAME)   do {                                                         \
./dist/gelf_dyn.c:              LIBELF_COPY_S32(dyn32, ds, d_tag);
./dist/gelf_rela.c:             LIBELF_COPY_S32(rela32, dr, r_addend);
$ grep d_tag elf_types.m4
        ``d_tag,        SWORD',
        ``d_tag,        SXWORD',
$ grep r_addend elf_types.m4
        `r_addend,      SWORD',
        `r_addend,      SXWORD',

only copy signed integer, unsigned integer is not used.

so previous comment is wrong, there’s no bug here.

[Takehiko NOZAKI]

BUGFIX: Issue #275 - TNF local patch for libelf LIBELF_COPY_U32/LIBELF_COPY_S32 range check cast u?int64_t for -Werror=type-limits

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