[PATCH 1/3] [binutils/readelf] Fix printing of dwarf4 .debug_str_offsets.dwo

[Tom de Vries]

When compiling a hello world with dwarf4 split dwarf:
...
$ gcc -gdwarf-4 -gsplit-dwarf hello.c -save-temps -dA
...
we have in a-hello.s these three initial entries in .debug_str_offsets:
...
	.section        .debug_str_offsets.dwo,"e",@progbits
	.4byte  0       // indexed string 0x0: short int
	.4byte  0xa     // indexed string 0x1: /home/vries/binutils
	.4byte  0x1f    // indexed string 0x2: main
...
but "readelf -ws a.out" starts at the third entry:
...
Contents of the .debug_str_offsets.dwo section (loaded from a-hello.dwo):

    Length: 0x30
       Index   Offset [String]
           0 00000000  main
...

This is a regression since commit 407115429b3 ("Modified changes for
split-dwarf and dwarf-5."), which introduced a variable
debug_str_offsets_hdr_len in display_debug_str_offsets.

Fix this by setting display_debug_str_offsets to 0 for the dwarf4 case.

PR 31734
---
 binutils/dwarf.c                                   |  1 +
 .../binutils-all/readelf-debug-str-offsets-dw4.d   | 14 ++++++++++++++
 .../binutils-all/readelf-debug-str-offsets-dw4.s   |  6 ++++++
 binutils/testsuite/binutils-all/readelf.exp        |  1 +
 4 files changed, 22 insertions(+)
 create mode 100644 binutils/testsuite/binutils-all/readelf-debug-str-offsets-dw4.d
 create mode 100644 binutils/testsuite/binutils-all/readelf-debug-str-offsets-dw4.s

diff --git a/binutils/dwarf.c b/binutils/dwarf.c
index c5ccc50dae7..8125c64e1b6 100644
--- a/binutils/dwarf.c
+++ b/binutils/dwarf.c
@@ -7969,6 +7969,7 @@ display_debug_str_offsets (struct dwarf_section *section,
 	  length = section->size;
 	  curr   = section->start;
 	  entries_end = end;
+	  debug_str_offsets_hdr_len = 0;
 
 	  printf (_("    Length: %#" PRIx64 "\n"), length);
 	  printf (_("       Index   Offset [String]\n"));
diff --git a/binutils/testsuite/binutils-all/readelf-debug-str-offsets-dw4.d b/binutils/testsuite/binutils-all/readelf-debug-str-offsets-dw4.d
new file mode 100644
index 00000000000..23581e70f3e
--- /dev/null
+++ b/binutils/testsuite/binutils-all/readelf-debug-str-offsets-dw4.d
@@ -0,0 +1,14 @@
+#name: readelf -ws readelf-debug-str-offsets-dw4
+#source: readelf-debug-str-offsets-dw4.s
+#readelf: -ws
+
+Contents of the .debug_str.dwo section:
+
+  0x00000000 46495253 54005345 434f4e44 00       FIRST.SECOND.
+
+Contents of the .debug_str_offsets.dwo section:
+
+    Length: 0x8
+       Index   Offset \[String\]
+           0 00000000  FIRST
+           1 00000006  SECOND
diff --git a/binutils/testsuite/binutils-all/readelf-debug-str-offsets-dw4.s b/binutils/testsuite/binutils-all/readelf-debug-str-offsets-dw4.s
new file mode 100644
index 00000000000..68f64dde234
--- /dev/null
+++ b/binutils/testsuite/binutils-all/readelf-debug-str-offsets-dw4.s
@@ -0,0 +1,6 @@
+	.section	.debug_str.dwo,"MS",@progbits,1
+	.string	"FIRST"
+	.string	"SECOND"
+	.section	.debug_str_offsets.dwo,"MS",@progbits,1
+	.4byte 0
+	.4byte 6
diff --git a/binutils/testsuite/binutils-all/readelf.exp b/binutils/testsuite/binutils-all/readelf.exp
index 09ed75f8761..9f20cb42812 100644
--- a/binutils/testsuite/binutils-all/readelf.exp
+++ b/binutils/testsuite/binutils-all/readelf.exp
@@ -402,6 +402,7 @@ if {[which $AS] != 0} then {
     run_dump_test "retain1b"
     run_dump_test "readelf-maskos-1a"
     run_dump_test "readelf-maskos-1b"
+    run_dump_test "readelf-debug-str-offsets-dw4"
     if {![istarget *-*-hpux*]} then {
 	run_dump_test pr26548
 	if {![binutils_assemble_flags $srcdir/$subdir/pr26548.s tmpdir/pr26548e.o {--defsym ERROR=1}]} then {

base-commit: 414aa6987f21a814851e5f3113388a3616993fa3
-- 
2.35.3