Commit Graph

2 Commits

Author SHA1 Message Date
Fangrui Song c3bc697974 [yaml2obj] Write the section header table after section contents
Linkers (ld.bfd/gold/lld) place the section header table at the very
end. This allows tools to strip it, which is optional in executable/shared objects.
In addition, if we add or section, the size of the section header table
will change. Placing the section header table in the end keeps section
offsets unchanged.

yaml2obj currently places the section header table immediately after the
program header. Follow what linkers do to make offset updating easier.

Reviewed By: grimar

Differential Revision: https://reviews.llvm.org/D67221

llvm-svn: 371074
2019-09-05 14:25:57 +00:00
Jordan Rupprecht f8f9d65f85 [llvm-objcopy] Fix SHT_GROUP ordering.
Summary:
When llvm-objcopy sorts sections during finalization, it only sorts based on the offset, which can cause the group section to come after the sections it contains. This causes link failures when using gold to link objects created by llvm-objcopy.

Fix this for now by copying GNU objcopy's behavior of placing SHT_GROUP sections first. In the future, we may want to remove this sorting entirely to more closely preserve the input file layout.

This fixes https://bugs.llvm.org/show_bug.cgi?id=42052.

Reviewers: jakehehrlich, jhenderson, MaskRay, espindola, alexshap

Reviewed By: MaskRay

Subscribers: phuongtrang148993, emaste, arichardson, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62620

llvm-svn: 362973
2019-06-10 18:35:01 +00:00