Don't merge 2 sections with different SHF_EXCLUDE

SEC_EXCLUDE is ignored when doing a relocatable link.  But we can't
merge 2 input sections with the same name when only one of them has
SHF_EXCLUDE.

	PR ld/20528
	* emultempl/elf32.em (gld${EMULATION_NAME}_place_orphan): Don't
	merge 2 sections with different SHF_EXCLUDE.
	* testsuite/ld-elf/pr20528a.d: New file.
	* testsuite/ld-elf/pr20528a.s: Likewise.
	* testsuite/ld-elf/pr20528b.d: Likewise.
	* testsuite/ld-elf/pr20528b.s: Likewise.

6 files changed, 48 insertions, 1 deletions

diff --git a/ld/ChangeLog b/ld/ChangeLog
index 988cb65..c5367a3 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,13 @@
+2016-09-29  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/20528
+	* emultempl/elf32.em (gld${EMULATION_NAME}_place_orphan): Don't
+	merge 2 sections with different SHF_EXCLUDE.
+	* testsuite/ld-elf/pr20528a.d: New file.
+	* testsuite/ld-elf/pr20528a.s: Likewise.
+	* testsuite/ld-elf/pr20528b.d: Likewise.
+	* testsuite/ld-elf/pr20528b.s: Likewise.
+
 2016-09-28  Christophe Lyon  <christophe.lyon@linaro.org>
 
 	PR ld/20608
diff --git a/ld/emultempl/elf32.em b/ld/emultempl/elf32.em
index 8461b1d..2815a3e 100644
--- a/ld/emultempl/elf32.em
+++ b/ld/emultempl/elf32.em
@@ -1907,9 +1907,16 @@ gld${EMULATION_NAME}_place_orphan (asection *s,
 	   lang_insert_orphan to create a new output section.  */
 	constraint = SPECIAL;
 
+	/* SEC_EXCLUDE is cleared when doing a relocatable link.  But
+	   we can't merge 2 input sections with the same name when only
+	   one of them has SHF_EXCLUDE.  */
 	if (os->bfd_section != NULL
 	    && (os->bfd_section->flags == 0
-		|| (((s->flags ^ os->bfd_section->flags)
+		|| ((!bfd_link_relocatable (&link_info)
+		     || (((elf_section_flags (s)
+			  ^ elf_section_flags (os->bfd_section))
+			 & SHF_EXCLUDE) == 0))
+		    && ((s->flags ^ os->bfd_section->flags)
 		     & (SEC_LOAD | SEC_ALLOC)) == 0
 		    && _bfd_elf_match_sections_by_type (link_info.output_bfd,
 							os->bfd_section,
diff --git a/ld/testsuite/ld-elf/pr20528a.d b/ld/testsuite/ld-elf/pr20528a.d
new file mode 100644
index 0000000..00d0a7a
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr20528a.d
@@ -0,0 +1,9 @@
+#source: pr20528a.s
+#source: pr20528b.s
+#ld: -r
+#readelf: -S --wide
+
+#...
+[ 	]*\[.*\][ 	]+\.text.startup[ 	]+PROGBITS.*[ 	]+AX[   ]+.*
+[ 	]*\[.*\][ 	]+\.text.startup[ 	]+PROGBITS.*[ 	]+AXE[   ]+.*
+#pass
diff --git a/ld/testsuite/ld-elf/pr20528a.s b/ld/testsuite/ld-elf/pr20528a.s
new file mode 100644
index 0000000..523bc6f
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr20528a.s
@@ -0,0 +1,6 @@
+        .text
+        .section        .text.startup,"ax",%progbits
+        .globl  main
+        .type   main, %function
+main:
+	.byte 0
diff --git a/ld/testsuite/ld-elf/pr20528b.d b/ld/testsuite/ld-elf/pr20528b.d
new file mode 100644
index 0000000..3ae6153
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr20528b.d
@@ -0,0 +1,9 @@
+#source: pr20528b.s
+#source: pr20528a.s
+#ld: -r
+#readelf: -S --wide
+
+#...
+[ 	]*\[.*\][ 	]+\.text.startup[ 	]+PROGBITS.*[ 	]+AXE[   ]+.*
+[ 	]*\[.*\][ 	]+\.text.startup[ 	]+PROGBITS.*[ 	]+AX[   ]+.*
+#pass
diff --git a/ld/testsuite/ld-elf/pr20528b.s b/ld/testsuite/ld-elf/pr20528b.s
new file mode 100644
index 0000000..9c41e8b
--- /dev/null
+++ b/ld/testsuite/ld-elf/pr20528b.s
@@ -0,0 +1,6 @@
+        .text
+        .section        .text.startup,"axe",%progbits
+        .globl  main1
+        .type   main1, %function
+main1:
+	.byte 0