[PATCH] D31255: Force @{init, fini}_array if section name starts with ".{init, fini}_array.".

[Rui Ueyama via Phabricator via llvm-commits]

ruiu updated this revision to Diff 92691.
ruiu added a comment.

- Do not use template.


https://reviews.llvm.org/D31255

Files:
  lld/ELF/InputSection.cpp
  lld/test/ELF/init-fini-progbits.s


Index: lld/test/ELF/init-fini-progbits.s
===================================================================
--- /dev/null
+++ lld/test/ELF/init-fini-progbits.s
@@ -0,0 +1,19 @@
+// REQUIRES: x86
+
+// RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
+// RUN: ld.lld %t -o %t.exe
+// RUN: llvm-readobj -sections %t.exe | FileCheck %s
+
+// CHECK:      Name: .init_array
+// CHECK-NEXT: Type: SHT_INIT_ARRAY
+// CHECK:      Name: .fini_array
+// CHECK-NEXT: Type: SHT_FINI_ARRAY
+
+.globl _start
+_start:
+  nop
+
+.section .init_array.100, "aw", @progbits
+  .byte 0
+.section .fini_array.100, "aw", @progbits
+  .byte 0
Index: lld/ELF/InputSection.cpp
===================================================================
--- lld/ELF/InputSection.cpp
+++ lld/ELF/InputSection.cpp
@@ -71,11 +71,30 @@
   this->Alignment = V;
 }
 
+// GNU assembler 2.24 and LLVM 4.0.0's MC (the newest release as of
+// March 2017) fail to infer section types for sections starting with
+// ".init_array." or ".fini_array.". They set SHT_PROGBITS instead. As a
+// result, the following assembler directive creates ".init_array.100"
+// with SHT_PROGBITS, while it should be SHF_INIT_ARRAY, for example.
+//
+//   .section .init_array.100, "aw"
+//
+// This function forces SHT_{INIT,FINI}_ARRAY so that we can handle
+// incorrect inputs as if they were correct from the beginning.
+static uint32_t getType(uint64_t Type, StringRef Name) {
+  if (Type == SHT_PROGBITS && Name.startswith(".init_array."))
+    return SHT_INIT_ARRAY;
+  if (Type == SHT_PROGBITS && Name.startswith(".fini_array."))
+    return SHT_FINI_ARRAY;
+  return Type;
+}
+
 template <class ELFT>
 InputSectionBase::InputSectionBase(elf::ObjectFile<ELFT> *File,
                                    const typename ELFT::Shdr *Hdr,
                                    StringRef Name, Kind SectionKind)
-    : InputSectionBase(File, Hdr->sh_flags & ~SHF_INFO_LINK, Hdr->sh_type,
+    : InputSectionBase(File, Hdr->sh_flags & ~SHF_INFO_LINK,
+                       getType(Hdr->sh_type, Name),
                        Hdr->sh_entsize, Hdr->sh_link, Hdr->sh_info,
                        Hdr->sh_addralign, getSectionContents(File, Hdr), Name,
                        SectionKind) {


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D31255.92691.patch
Type: text/x-patch
Size: 2248 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20170322/3952ef9f/attachment.bin>