[binutils-gdb] Don't check undefined symbol for IFUNC reloc

[H.J.Lu <hjl at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=bf52d7c72035679e6b3ab601133c56a4388f4dc9

commit bf52d7c72035679e6b3ab601133c56a4388f4dc9
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Wed Jun 15 10:35:38 2016 -0700

    Don't check undefined symbol for IFUNC reloc
    
    Since x86 elf_*_check_relocs is called after all symbols have been
    resolved, there is no need to check undefined symbols for relocations
    against IFUNC symbols.
    
    bfd/
    
    	* elf32-i386.c (elf_i386_check_relocs): Don't check undefined
    	symbols for relocations against IFUNC symbols.
    	* elf64-x86-64.c (elf_x86_64_check_relocs): Likewise.
    
    ld/
    
    	* testsuite/ld-i386/i386.exp: Run pr19636-2e-nacl.
    	* testsuite/ld-i386/pr19636-2e.d: Skip for NaCl targets.
    	Remove .rel.plt section.
    	* testsuite/ld-i386/pr19636-2e-nacl.d: New file.

Diff:
---
 bfd/elf32-i386.c                       | 11 ++++-------
 bfd/elf64-x86-64.c                     | 11 ++++-------
 ld/testsuite/ld-i386/i386.exp          |  1 +
 ld/testsuite/ld-i386/pr19636-2e-nacl.d | 21 +++++++++++++++++++++
 ld/testsuite/ld-i386/pr19636-2e.d      |  5 +----
 5 files changed, 31 insertions(+), 18 deletions(-)

diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c
index a519778..2b7de33 100644
--- a/bfd/elf32-i386.c
+++ b/bfd/elf32-i386.c
@@ -2149,15 +2149,12 @@ elf_i386_check_relocs (bfd *abfd,
 	  if (eh != NULL && (sec->flags & SEC_CODE) != 0)
 	    eh->has_non_got_reloc = 1;
 do_relocation:
-	  /* STT_GNU_IFUNC symbol must go through PLT even if it is
-	     locally defined and undefined symbol may turn out to be
-	     a STT_GNU_IFUNC symbol later.  */
+	  /* We are called after all symbols have been resolved.  Only
+	     relocation against STT_GNU_IFUNC symbol must go through
+	     PLT.  */
 	  if (h != NULL
 	      && (bfd_link_executable (info)
-		  || ((h->type == STT_GNU_IFUNC
-		       || h->root.type == bfd_link_hash_undefweak
-		       || h->root.type == bfd_link_hash_undefined)
-		      && SYMBOLIC_BIND (info, h))))
+		  || h->type == STT_GNU_IFUNC))
 	    {
 	      /* If this reloc is in a read-only section, we might
 		 need a copy reloc.  We can't check reliably at this
diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c
index 9044aab..57a3c73 100644
--- a/bfd/elf64-x86-64.c
+++ b/bfd/elf64-x86-64.c
@@ -2541,15 +2541,12 @@ elf_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info,
 pointer:
 	  if (eh != NULL && (sec->flags & SEC_CODE) != 0)
 	    eh->has_non_got_reloc = 1;
-	  /* STT_GNU_IFUNC symbol must go through PLT even if it is
-	     locally defined and undefined symbol may turn out to be
-	     a STT_GNU_IFUNC symbol later.  */
+	  /* We are called after all symbols have been resolved.  Only
+	     relocation against STT_GNU_IFUNC symbol must go through
+	     PLT.  */
 	  if (h != NULL
 	      && (bfd_link_executable (info)
-		  || ((h->type == STT_GNU_IFUNC
-		       || h->root.type == bfd_link_hash_undefweak
-		       || h->root.type == bfd_link_hash_undefined)
-		      && SYMBOLIC_BIND (info, h))))
+		  || h->type == STT_GNU_IFUNC))
 	    {
 	      /* If this reloc is in a read-only section, we might
 		 need a copy reloc.  We can't check reliably at this
diff --git a/ld/testsuite/ld-i386/i386.exp b/ld/testsuite/ld-i386/i386.exp
index 8468920..98f0b1c 100644
--- a/ld/testsuite/ld-i386/i386.exp
+++ b/ld/testsuite/ld-i386/i386.exp
@@ -372,6 +372,7 @@ run_dump_test "pr19636-2c-nacl"
 run_dump_test "pr19636-2d"
 run_dump_test "pr19636-2d-nacl"
 run_dump_test "pr19636-2e"
+run_dump_test "pr19636-2e-nacl"
 run_dump_test "pr19636-3a"
 run_dump_test "pr19636-3b"
 run_dump_test "pr19636-3c"
diff --git a/ld/testsuite/ld-i386/pr19636-2e-nacl.d b/ld/testsuite/ld-i386/pr19636-2e-nacl.d
new file mode 100644
index 0000000..f791128
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr19636-2e-nacl.d
@@ -0,0 +1,21 @@
+#source: pr19636-2.s
+#as: --32 -mrelax-relocations=no
+#ld: -shared -Bsymbolic -m elf_i386
+#readelf : -r --wide --dyn-syms
+#target: i?86-*-nacl* x86_64-*-nacl*
+
+Relocation section '\.rel\.dyn' at offset [0x0-9a-f]+ contains 3 entries:
+ +Offset +Info +Type +Sym. Value +Symbol's Name
+[0-9a-f]+ +[0-9a-f]+ +R_386_32 +0+ +func
+[0-9a-f]+ +[0-9a-f]+ +R_386_PC32 +0+ +func
+[0-9a-f]+ +[0-9a-f]+ +R_386_GLOB_DAT +0+ +func
+
+Relocation section '\.rel\.plt' at offset [0x0-9a-f]+ contains 1 entries:
+ +Offset +Info +Type +Sym. Value +Symbol's Name
+[0-9a-f]+ +[0-9a-f]+ +R_386_JUMP_SLOT +0+ +func
+
+Symbol table '\.dynsym' contains [0-9]+ entries:
+ +Num: +Value +Size Type +Bind +Vis +Ndx Name
+#...
+ +[0-9]+: +[a-f0-9]+ +0 +NOTYPE +WEAK +DEFAULT +UND +func
+#pass
diff --git a/ld/testsuite/ld-i386/pr19636-2e.d b/ld/testsuite/ld-i386/pr19636-2e.d
index c985242..148e306 100644
--- a/ld/testsuite/ld-i386/pr19636-2e.d
+++ b/ld/testsuite/ld-i386/pr19636-2e.d
@@ -2,6 +2,7 @@
 #as: --32 -mrelax-relocations=no
 #ld: -shared -Bsymbolic -m elf_i386
 #readelf : -r --wide --dyn-syms
+#notarget: i?86-*-nacl* x86_64-*-nacl*
 
 Relocation section '\.rel\.dyn' at offset [0x0-9a-f]+ contains 3 entries:
  +Offset +Info +Type +Sym. Value +Symbol's Name
@@ -9,10 +10,6 @@ Relocation section '\.rel\.dyn' at offset [0x0-9a-f]+ contains 3 entries:
 [0-9a-f]+ +[0-9a-f]+ +R_386_PC32 +0+ +func
 [0-9a-f]+ +[0-9a-f]+ +R_386_GLOB_DAT +0+ +func
 
-Relocation section '\.rel\.plt' at offset [0x0-9a-f]+ contains 1 entries:
- +Offset +Info +Type +Sym. Value +Symbol's Name
-[0-9a-f]+ +[0-9a-f]+ +R_386_JUMP_SLOT +0+ +func
-
 Symbol table '\.dynsym' contains [0-9]+ entries:
  +Num: +Value +Size Type +Bind +Vis +Ndx Name
 #...