Commit Graph

2 Commits

Author SHA1 Message Date
Georgii Rymar a7a447be0f [yaml2obj] - ProgramHeaders: introduce FirstSec/LastSec instead of Sections list.
Imagine we have a YAML declaration of few sections: `foo1`, `<unnamed 2>`, `foo3`, `foo4`.

To put them into segment we can do (1*):

```
Sections:
 - Section: foo1
 - Section: foo4
```

or we can use (2*):

```
Sections:
 - Section: foo1
 - Section: foo3
 - Section: foo4
```

or (3*) :

```
Sections:
 - Section: foo1
## "(index 2)" here is a name that we automatically created for a unnamed section.
 - Section: (index 2)
 - Section: foo3
 - Section: foo4
```

It looks really confusing that we don't have to list all of sections.

At first I've tried to make this rule stricter and report an error when there is a gap
(i.e. when a section is included into segment, but not listed explicitly).
This did not work perfect, because such approach conflicts with unnamed sections/fills (see (3*)).

This patch drops "Sections" key and introduces 2 keys instead: `FirstSec` and `LastSec`.
Both are optional.

Differential revision: https://reviews.llvm.org/D90458
2020-11-09 13:00:50 +03:00
James Henderson 38cb238f75 [llvm-objcopy]Allow llvm-objcopy to be used on an ELF file with no section headers
This patch fixes https://bugs.llvm.org/show_bug.cgi?id=41293 and
https://bugs.llvm.org/show_bug.cgi?id=41045. llvm-objcopy assumed that
it could always read a section header string table. This isn't the case
when the sections were previously all stripped, and the e_shstrndx field
was set to 0. This patch fixes this. It also fixes a double space in an
error message relating to this issue, and prevents llvm-objcopy from
adding extra space for non-existent section headers, meaning that
--strip-sections on the output of a previous --strip-sections run
produces identical output, simplifying the test.

Reviewed by: rupprecht, grimar

Differential Revision: https://reviews.llvm.org/D59989

llvm-svn: 357475
2019-04-02 14:11:13 +00:00