[LLMV] set OpenBSD's ELFOSABI by default

Ericson2314 · Ericson2314 · commit 9da46ac6e78e · 2024-07-10T09:46:01.000-04:00
This matches what is done for FreeBSD. OpenBSD has a few special program header types, and other such ELF extensions. Setting the ELFOSABI like so will allow LLD to support them without needlessly impacting non-OpenBSD ELFs. Testing strategy matches 8738c5b / D107748. Added one for FreeBSD too for good measure.
diff --git a/llvm/include/llvm/MC/MCELFObjectWriter.h b/llvm/include/llvm/MC/MCELFObjectWriter.h
@@ -78,6 +78,8 @@ class MCELFObjectTargetWriter : public MCObjectTargetWriter {
         return ELF::ELFOSABI_FREEBSD;
       case Triple::Solaris:
         return ELF::ELFOSABI_SOLARIS;
+      case Triple::OpenBSD:
+        return ELF::ELFOSABI_OPENBSD;
       default:
         return ELF::ELFOSABI_NONE;
     }
diff --git a/llvm/test/MC/ELF/osabi-freebsd.s b/llvm/test/MC/ELF/osabi-freebsd.s
@@ -0,0 +1,2 @@
+# RUN: llvm-mc -filetype obj -triple amd64-freebsd %s | llvm-readobj -hS - | FileCheck %s
+# CHECK: OS/ABI: FreeBSD
diff --git a/llvm/test/MC/ELF/osabi-openbsd.s b/llvm/test/MC/ELF/osabi-openbsd.s
@@ -0,0 +1,2 @@
+# RUN: llvm-mc -filetype obj -triple amd64-openbsd %s | llvm-readobj -hS - | FileCheck %s
+# CHECK: OS/ABI: OpenBSD

Original file line number	Diff line number	Diff line change
`@@ -78,6 +78,8 @@ class MCELFObjectTargetWriter : public MCObjectTargetWriter {`
`78`	`78`	`return ELF::ELFOSABI_FREEBSD;`
`79`	`79`	`case Triple::Solaris:`
`80`	`80`	`return ELF::ELFOSABI_SOLARIS;`
	`81`	`+ case Triple::OpenBSD:`
	`82`	`+ return ELF::ELFOSABI_OPENBSD;`
`81`	`83`	`default:`
`82`	`84`	`return ELF::ELFOSABI_NONE;`
`83`	`85`	`}`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	`+# RUN: llvm-mc -filetype obj -triple amd64-freebsd %s \| llvm-readobj -hS - \| FileCheck %s`
	`2`	`+# CHECK: OS/ABI: FreeBSD`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	`+# RUN: llvm-mc -filetype obj -triple amd64-openbsd %s \| llvm-readobj -hS - \| FileCheck %s`
	`2`	`+# CHECK: OS/ABI: OpenBSD`