[PATCH] D33019: [ELF] Define __ehdr_start unconditionally even when using linker script
Petr Hosek via Phabricator via llvm-commits
llvm-commits at lists.llvm.org
Wed May 10 09:33:53 PDT 2017
This revision was automatically updated to reflect the committed changes.
Closed by commit rL302687: [ELF] Define __ehdr_start unconditionally even when using linker script (authored by phosek).
Changed prior to commit:
https://reviews.llvm.org/D33019?vs=98362&id=98478#toc
Repository:
rL LLVM
https://reviews.llvm.org/D33019
Files:
lld/trunk/ELF/Writer.cpp
lld/trunk/test/ELF/linkerscript/ehdr_start.s
Index: lld/trunk/test/ELF/linkerscript/ehdr_start.s
===================================================================
--- lld/trunk/test/ELF/linkerscript/ehdr_start.s
+++ lld/trunk/test/ELF/linkerscript/ehdr_start.s
@@ -2,9 +2,17 @@
# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t.o
# RUN: echo "SECTIONS { }" > %t.script
-# RUN: not ld.lld %t.o -script %t.script -o %t 2>&1 | FileCheck %s
-# CHECK: error: undefined symbol: __ehdr_start
-# CHECK: >>> referenced by {{.*}}:(.text+0x0)
+# RUN: ld.lld %t.o -script %t.script -o %t
+# RUN: llvm-readobj -symbols %t | FileCheck %s
+# CHECK: Name: __ehdr_start (1)
+# CHECK-NEXT: Value: 0x0
+# CHECK-NEXT: Size: 0
+# CHECK-NEXT: Binding: Local (0x0)
+# CHECK-NEXT: Type: None (0x0)
+# CHECK-NEXT: Other [ (0x2)
+# CHECK-NEXT: STV_HIDDEN (0x2)
+# CHECK-NEXT: ]
+# CHECK-NEXT: Section: .text (0x1)
.text
.global _start, __ehdr_start
Index: lld/trunk/ELF/Writer.cpp
===================================================================
--- lld/trunk/ELF/Writer.cpp
+++ lld/trunk/ELF/Writer.cpp
@@ -859,13 +859,16 @@
if (!In<ELFT>::DynSymTab)
Symtab<ELFT>::X->addIgnored("__tls_get_addr");
+ // __ehdr_start is the location of ELF file headers. Note that we define
+ // this symbol unconditionally even when using a linker script, which
+ // differs from the behavior implemented by GNU linker which only define
+ // this symbol if ELF headers are in the memory mapped segment.
+ addOptionalRegular<ELFT>("__ehdr_start", Out::ElfHeader, 0, STV_HIDDEN);
+
// If linker script do layout we do not need to create any standart symbols.
if (Script->Opt.HasSections)
return;
- // __ehdr_start is the location of ELF file headers.
- addOptionalRegular<ELFT>("__ehdr_start", Out::ElfHeader, 0, STV_HIDDEN);
-
auto Add = [](StringRef S) {
return addOptionalRegular<ELFT>(S, Out::ElfHeader, 0, STV_DEFAULT);
};
-------------- next part --------------
A non-text attachment was scrubbed...
Name: D33019.98478.patch
Type: text/x-patch
Size: 1939 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20170510/da80565c/attachment.bin>
More information about the llvm-commits
mailing list