PR27100, final link failed: bad value

The failure on this PR is due to using the same bfd section for
multiple output sections.  Commit 21401fc7bf managed to create
duplicate linker script output section statements, but not the actual
bfd sections.

	PR 27100
	* ldlang.h (lang_output_section_statement_type): Add dup_output.
	* ldlang.c (lang_output_section_statement_lookup): Set dup_output.
	(init_os): Test dup_output rather than constraint.
	* testsuite/ld-scripts/pr27100.d,
	* testsuite/ld-scripts/pr27100.s,
	* testsuite/ld-scripts/pr27100.t: New test.
	* testsuite/ld-scripts/data.exp: Run it.  Don't exclude aout here.
	* testsuite/ld-scripts/data.d: Do so here instead.
	* testsuite/ld-scripts/fill.d: Likewise.
	* testsuite/ld-scripts/fill16.d: Likewise.

ld/ChangeLog

@@ -1,3 +1,17 @@
+2020-12-24  Alan Modra  <amodra@gmail.com>
+
+	PR 27100
+	* ldlang.h (lang_output_section_statement_type): Add dup_output.
+	* ldlang.c (lang_output_section_statement_lookup): Set dup_output.
+	(init_os): Test dup_output rather than constraint.
+	* testsuite/ld-scripts/pr27100.d,
+	* testsuite/ld-scripts/pr27100.s,
+	* testsuite/ld-scripts/pr27100.t: New test.
+	* testsuite/ld-scripts/data.exp: Run it.  Don't exclude aout here.
+	* testsuite/ld-scripts/data.d: Do so here instead.
+	* testsuite/ld-scripts/fill.d: Likewise.
+	* testsuite/ld-scripts/fill16.d: Likewise.
+
 2020-12-23  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* NEWS: Mention LAM_U48 and LAM_U57 support.

ld/ldlang.c

@@ -1526,6 +1526,8 @@ lang_output_section_statement_lookup (const char *name,
 
   entry->s.output_section_statement.name = name;
   entry->s.output_section_statement.constraint = constraint;
+  entry->s.output_section_statement.dup_output = (create == 2
+						  || constraint == SPECIAL);
   return &entry->s.output_section_statement;
 }
 
@@ -2387,7 +2389,7 @@ init_os (lang_output_section_statement_type *s, flagword flags)
   if (strcmp (s->name, DISCARD_SECTION_NAME) == 0)
     einfo (_("%F%P: illegal use of `%s' section\n"), DISCARD_SECTION_NAME);
 
-  if (s->constraint != SPECIAL)
+  if (!s->dup_output)
     s->bfd_section = bfd_get_section_by_name (link_info.output_bfd, s->name);
   if (s->bfd_section == NULL)
     s->bfd_section = bfd_make_section_anyway_with_flags (link_info.output_bfd,

ld/ldlang.h

@@ -173,6 +173,9 @@ typedef struct lang_output_section_statement_struct
   unsigned int after_end : 1;
   /* If this section uses the alignment of its input sections.  */
   unsigned int align_lma_with_input : 1;
+  /* If script has duplicate output section statements of the same name
+     create duplicate output sections.  */
+  unsigned int dup_output : 1;
 } lang_output_section_statement_type;
 
 typedef struct

ld/testsuite/ld-scripts/data.d

@@ -1,6 +1,7 @@
 #source: data.s
 #ld: -T data.t
 #objdump: -s -j .text
+#notarget: [is_aout_format]
 #xfail: tic4x-*-* tic54x-*-*
 
 .*:     file format .*

ld/testsuite/ld-scripts/data.exp

@@ -19,14 +19,6 @@
 # Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
 # MA 02110-1301, USA.
 
-# An a.out "objdump -s -j .text" has the file header visible inside the
-# text segment, confusing run_dump_test.
-if {[is_aout_format]} {
-	unsupported data
-	unsupported fill
-	return
-}
-
 set old_LDFLAGS $LDFLAGS
 if { [is_xcoff_format] } then {
     set LDFLAGS "$LDFLAGS -bnogc"
@@ -35,5 +27,6 @@ if { [is_xcoff_format] } then {
 run_dump_test data
 run_dump_test fill
 run_dump_test fill16
+run_dump_test pr27100
 
 set LDFLAGS $old_LDFLAGS

ld/testsuite/ld-scripts/fill.d

@@ -3,6 +3,7 @@
 #source: fill_2.s
 #ld: -T fill.t
 #objdump: -s -j .text
+#notarget: [is_aout_format]
 #skip: ia64-*-* mips*-*-freebsd* mips*-*-gnu* mips*-*-irix* mips*-*-kfreebsd*
 #skip: mips*-*-linux* mips*-*-netbsd* mips*-*-openbsd* mips*-*-sysv4*
 #skip: tilegx*-*-* tilepro-*-* x86_64-*-cygwin x86_64-*-mingw* x86_64-*-pe*

ld/testsuite/ld-scripts/fill16.d

@@ -3,6 +3,7 @@
 #source: fill16_2.s
 #ld: -T fill.t
 #objdump: -s -j .text
+#notarget: [is_aout_format]
 #skip: arm-*-coff i[3-7]86-*-coff [is_xcoff_format]
 #xfail: alpha*-*-*ecoff sh-*-pe sparc*-*-coff
 #xfail: tic30-*-coff tic4x-*-* tic54x-*-* z8k-*-*

ld/testsuite/ld-scripts/pr27100.d

@@ -0,0 +1,10 @@
+#ld: -r -T pr27100.t
+#objdump: -h
+#notarget: [is_aout_format]
+#xfail: alpha*-*-*vms* mmix-*-* *c54x-*-* [is_xcoff_format]
+
+#...
+.* \.data +0+60 .*
+#...
+.* \.data +0+10 .*
+#pass

ld/testsuite/ld-scripts/pr27100.s

@@ -0,0 +1,2 @@
+ .data
+ .space 80

ld/testsuite/ld-scripts/pr27100.t

@@ -0,0 +1,2 @@
+SECTIONS { .data ALIGN (16) : { aa = .; LONG(0xdeadbeef); . = ALIGN (16); } }
+SECTIONS { .data ALIGN (16) : { bb = .; LONG(0x00c0ffee); . = ALIGN (16); } }