re PR lto/81968 (early lto debug objects make Solaris ld SEGV)

2018-01-11  Richard Biener  <rguenther@suse.de>
	Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

	PR lto/81968
	libiberty/
	* simple-object-common.h (struct simple_object_functions):
	Change copy_lto_debug_sections callback signature.
	* simple-object-elf.c (SHN_HIRESERVE, SHT_SYMTAB_SHNDX,
	SHF_INFO_LINK): Add defines.
	(simple_object_elf_copy_lto_debug_sections): Instead of
	leaving not to be copied sections empty unnamed SHT_NULL
	remove them from the target section headers and adjust section
	reference everywhere.  Handle SHN_XINDEX in the symbol table
	processing properly.
	* simple-object.c (handle_lto_debug_sections): Change
	interface to return a modified string and handle renaming
	of relocation sections.

Co-Authored-By: Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE>

From-SVN: r256528

libiberty/ChangeLog

+2018-01-11  Richard Biener  <rguenther@suse.de>
+	Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
+
+	PR lto/81968
+	* simple-object-common.h (struct simple_object_functions):
+	Change copy_lto_debug_sections callback signature.
+	* simple-object-elf.c (SHN_HIRESERVE, SHT_SYMTAB_SHNDX,
+	SHF_INFO_LINK): Add defines.
+	(simple_object_elf_copy_lto_debug_sections): Instead of
+	leaving not to be copied sections empty unnamed SHT_NULL
+	remove them from the target section headers and adjust section
+	reference everywhere.  Handle SHN_XINDEX in the symbol table
+	processing properly.
+	* simple-object.c (handle_lto_debug_sections): Change
+	interface to return a modified string and handle renaming
+	of relocation sections.
+
 2018-01-10  Daniel van Gerpen  <daniel@vangerpen.de>
 
 	* argv.c (expandargv): Correct check for dynamically

libiberty/simple-object-common.h

@@ -145,7 +145,7 @@ struct simple_object_functions
   /* Copy LTO debug sections.  */
   const char *(*copy_lto_debug_sections) (simple_object_read *sobj,
 					  simple_object_write *dobj,
-					  int (*pfn) (const char **),
+					  char *(*pfn) (const char *),
 					  int *err);
 };
 

libiberty/simple-object.c

@@ -253,30 +253,38 @@ simple_object_find_section (simple_object_read *sobj, const char *name,
 /* Callback to identify and rename LTO debug sections by name.
    Returns 1 if NAME is a LTO debug section, 0 if not.  */
 
-static int
-handle_lto_debug_sections (const char **name)
+static char *
+handle_lto_debug_sections (const char *name)
 {
+  char *newname = XCNEWVEC (char, strlen (name) + 1);
+
   /* ???  So we can't use .gnu.lto_ prefixed sections as the assembler
      complains about bogus section flags.  Which means we need to arrange
      for that to be fixed or .gnu.debuglto_ marked as SHF_EXCLUDE (to make
      fat lto object tooling work for the fat part).  */
-  /* ???  For now this handles both .gnu.lto_ and .gnu.debuglto_ prefixed
-     sections.  */
-  /* Copy LTO debug sections and rename them to their non-LTO name.  */
-  if (strncmp (*name, ".gnu.debuglto_", sizeof (".gnu.debuglto_") - 1) == 0)
+  /* Also include corresponding reloc sections.  */
+  if (strncmp (name, ".rela", sizeof (".rela") - 1) == 0)
     {
-      *name = *name + sizeof (".gnu.debuglto_") - 1;
-      return 1;
+      strncpy (newname, name, sizeof (".rela") - 1);
+      name += sizeof (".rela") - 1;
     }
-  else if (strncmp (*name, ".gnu.lto_.debug_", sizeof (".gnu.lto_.debug_") -1) == 0)
+  else if (strncmp (name, ".rel", sizeof (".rel") - 1) == 0)
     {
-      *name = *name + sizeof (".gnu.lto_") - 1;
-      return 1;
+      strncpy (newname, name, sizeof (".rel") - 1);
+      name += sizeof (".rel") - 1;
     }
+  /* ???  For now this handles both .gnu.lto_ and .gnu.debuglto_ prefixed
+     sections.  */
+  /* Copy LTO debug sections and rename them to their non-LTO name.  */
+  if (strncmp (name, ".gnu.debuglto_", sizeof (".gnu.debuglto_") - 1) == 0)
+    return strcat (newname, name + sizeof (".gnu.debuglto_") - 1);
+  else if (strncmp (name, ".gnu.lto_.debug_",
+		    sizeof (".gnu.lto_.debug_") -1) == 0)
+    return strcat (newname, name + sizeof (".gnu.lto_") - 1);
   /* Copy over .note.GNU-stack section under the same name if present.  */
-  else if (strcmp (*name, ".note.GNU-stack") == 0)
-    return 1;
-  return 0;
+  else if (strcmp (name, ".note.GNU-stack") == 0)
+    return strcpy (newname, name);
+  return NULL;
 }
 
 /* Copy LTO debug sections.  */