[all-commits] [llvm/llvm-project] bb7d2b: [LLD][ELF] - Disambiguate "=fillexp" with a primar...

[Georgii Rymar via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: bb7d2b178022e8590f483714bd9bafa9d3f86e24
      https://github.com/llvm/llvm-project/commit/bb7d2b178022e8590f483714bd9bafa9d3f86e24
  Author: Georgii Rymar <grimar at accesssoftek.com>
  Date:   2020-03-19 (Thu, 19 Mar 2020)

  Changed paths:
    M lld/ELF/ScriptParser.cpp
    M lld/test/ELF/linkerscript/sections-padding.s

  Log Message:
  -----------
  [LLD][ELF] - Disambiguate "=fillexp" with a primary expression to allow =0x90 /DISCARD/

Fixes https://bugs.llvm.org/show_bug.cgi?id=44903

It is about the following case:

```
SECTIONS {
  .foo : { *(.foo) } =0x90909090
  /DISCARD/ : { *(.bar) }
}
```

Here while parsing the fill expression we treated the
"/" of "/DISCARD/" as operator.

With this change, suggested by Fangrui Song, we do
not allow expressions with operators (e.g. "0x1100 + 0x22")
that are not wrapped into round brackets. It should not
be an issue for users, but helps to resolve parsing ambiguity.

Differential revision: https://reviews.llvm.org/D74687