Stop the BFD library from treating annobin symbols as potential function symbols.

bfd	* elf.c (_bfd_elf_maybe_function_sym): Do not accept annobin
	symbols as potential function symbols.
	* elfnn-aarch64.c (elfNN_aarch64_maybe_function_sym): Likewise.
	* elf64-ppc.c (ppc64_elf_maybe_function_sym): Likewise.
	* elf32-arm.c (elf32_arm_maybe_function_sym): Likewise.

ld	* testsuite/ld-elf/anno-sym.s: New test source file.
	* testsuite/ld-elf/anno-sym.d: New test driver.
	* testsuite/ld-elf/anno-sym.l: New test error output.

1 files changed, 17 insertions, 6 deletions

diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c
index 08227f0..ed72de2 100644
--- a/bfd/elf64-ppc.c
+++ b/bfd/elf64-ppc.c
@@ -5534,14 +5534,25 @@ ppc64_elf_maybe_function_sym (const asymbol *sym, asection *sec,
 			      bfd_vma *code_off)
 {
   bfd_size_type size;
+  elf_symbol_type * elf_sym = (elf_symbol_type *) sym;
 
   if ((sym->flags & (BSF_SECTION_SYM | BSF_FILE | BSF_OBJECT
 		     | BSF_THREAD_LOCAL | BSF_RELC | BSF_SRELC)) != 0)
     return 0;
 
-  size = 0;
-  if (!(sym->flags & BSF_SYNTHETIC))
-    size = ((elf_symbol_type *) sym)->internal_elf_sym.st_size;
+  size = (sym->flags & BSF_SYNTHETIC) ? 0 : elf_sym->internal_elf_sym.st_size;
+
+  /* In theory we should check that the symbol's type satisfies
+     _bfd_elf_is_function_type(), but there are some function-like
+     symbols which would fail this test.  (eg _start).  Instead
+     we check for hidden, local, notype symbols with zero size.
+     This type of symbol is generated by the annobin plugin for gcc
+     and clang, and should not be considered to be a function symbol.  */
+  if (size == 0
+      && ((sym->flags & (BSF_SYNTHETIC | BSF_LOCAL)) == BSF_LOCAL)
+      && ELF_ST_TYPE (elf_sym->internal_elf_sym.st_info) == STT_NOTYPE
+      && ELF_ST_VISIBILITY (elf_sym->internal_elf_sym.st_other) == STV_HIDDEN)
+    return 0;
 
   if (strcmp (sym->section->name, ".opd") == 0)
     {
@@ -5585,9 +5596,9 @@ ppc64_elf_maybe_function_sym (const asymbol *sym, asection *sec,
 	return 0;
       *code_off = sym->value;
     }
-  if (size == 0)
-    size = 1;
-  return size;
+
+  /* Do not return 0 for the function's size.  */
+  return size ? size : 1;
 }
 
 /* Return true if symbol is a strong function defined in an ELFv2