[gdb/testsuite] Fix gdb.arch/amd64-entry-value-paramref.S

The file gdb.arch/amd64-entry-value-paramref.S contains a DIE for function
bar:
...
DIE29:  .uleb128 0x2    # (DIE (0x29) DW_TAG_subprogram)
        .ascii "bar\0"  # DW_AT_name
        .byte   0x1     # DW_AT_decl_file (gdb.arch/amd64-entry-value-paramref.cc)
        .byte   0x15    # DW_AT_decl_line
        .long   DIE45   # DW_AT_type
        .byte   0x1     # DW_AT_inline
...
which refers to DIE45:
...
DIE45:	.uleb128 0x4	# (DIE (0x45) DW_TAG_base_type)
	.byte	0x4	# DW_AT_byte_size
	.byte	0x5	# DW_AT_encoding
	.ascii "int\0"	# DW_AT_name
...
using a form DW_FORM_ref4:
...
	.uleb128 0x2	# (abbrev code)
	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
	.byte	0x1	# DW_children_yes
	...
	.uleb128 0x49	# (DW_AT_type)
	.uleb128 0x13	# (DW_FORM_ref4)
...

However, the DW_FORM_ref4 is a CU-relative reference, while using a label for
the value will result in a section-relative value.

So, if linked in object files contain dwarf info and are placed in the
.debug_info section before the compilation units generated from
amd64-entry-value-paramref.S, then the referenced type is at 0x108:
...
 <1><108>: Abbrev Number: 4 (DW_TAG_base_type)
    <109>   DW_AT_byte_size   : 4
    <10a>   DW_AT_encoding    : 5       (signed)
    <10b>   DW_AT_name        : int
...
but the reference will point to a non-existing DIE at 0x1cf:
...
 <1><f0>: Abbrev Number: 2 (DW_TAG_subprogram)
    <f1>   DW_AT_name        : bar
    <f5>   DW_AT_decl_file   : 1
    <f6>   DW_AT_decl_line   : 21
    <f7>   DW_AT_type        : <0x1cf>
    <fb>   DW_AT_inline      : 1        (inlined)
...
which happens to cause a GDB internal error described in PR23270 - "GDB
internal error: dwarf2read.c:18656: internal-error: could not find partial
DIE 0x1b7 in cache".

Fix the invalid DWARF by making the reference value CU-relative:
...
-       .long   DIE45   # DW_AT_type
+       .long   DIE45 - .Ldebug_info0   # DW_AT_type
...

Tested on x86_64-linux.

gdb/testsuite/ChangeLog:

2019-05-09  Tom de Vries  <tdevries@suse.de>

	* gdb.arch/amd64-entry-value-paramref.S: Make DW_FORM_ref4 references
	CU-relative.

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index a556eb3..47e82c4 100644 (file)
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-05-09  Tom de Vries  <tdevries@suse.de>
+
+       * gdb.arch/amd64-entry-value-paramref.S: Make DW_FORM_ref4 references
+       CU-relative.
+
 2019-05-08  Joel Brobecker  <brobecker@adacore.com>
 
        * gdb.ada/frame_arg_lang.exp: New testcase.

diff --git a/gdb/testsuite/gdb.arch/amd64-entry-value-paramref.S b/gdb/testsuite/gdb.arch/amd64-entry-value-paramref.S
index 7c12d13..2e59aae 100644 (file)
--- a/gdb/testsuite/gdb.arch/amd64-entry-value-paramref.S
+++ b/gdb/testsuite/gdb.arch/amd64-entry-value-paramref.S
@@ -121,32 +121,32 @@ DIE29:    .uleb128 0x2    # (DIE (0x29) DW_TAG_subprogram)
        .ascii "bar\0"  # DW_AT_name
        .byte   0x1     # DW_AT_decl_file (gdb.arch/amd64-entry-value-paramref.cc)
        .byte   0x15    # DW_AT_decl_line
-       .long   DIE45   # DW_AT_type
+       .long   DIE45 - .Ldebug_info0   # DW_AT_type
        .byte   0x1     # DW_AT_inline
 DIE39: .uleb128 0x3    # (DIE (0x39) DW_TAG_formal_parameter)
        .ascii "ref\0"  # DW_AT_name
        .byte   0x1     # DW_AT_decl_file (gdb.arch/amd64-entry-value-paramref.cc)
        .byte   0x15    # DW_AT_decl_line
-       .long   DIE4c   # DW_AT_type
+       .long   DIE4c - .Ldebug_info0   # DW_AT_type
        .byte   0       # end of children of DIE 0x29
 DIE45: .uleb128 0x4    # (DIE (0x45) DW_TAG_base_type)
        .byte   0x4     # DW_AT_byte_size
        .byte   0x5     # DW_AT_encoding
        .ascii "int\0"  # DW_AT_name
 DIE4c: .uleb128 0x5    # (DIE (0x4c) DW_TAG_const_type)
-       .long   DIE51   # DW_AT_type
+       .long   DIE51 - .Ldebug_info0   # DW_AT_type
 DIE51: .uleb128 0x6    # (DIE (0x51) DW_TAG_reference_type)
        .byte   0x8     # DW_AT_byte_size
-       .long   DIE45   # DW_AT_type
+       .long   DIE45 - .Ldebug_info0   # DW_AT_type
 DIE57: .uleb128 0x7    # (DIE (0x57) DW_TAG_subprogram)
-       .long   DIE29   # DW_AT_abstract_origin
+       .long   DIE29 - .Ldebug_info0   # DW_AT_abstract_origin
        .quad   .LFB2   # DW_AT_low_pc
        .quad   .LFE2-.LFB2     # DW_AT_high_pc
        .uleb128 0x1    # DW_AT_frame_base
        .byte   0x9c    # DW_OP_call_frame_cfa
                        # DW_AT_GNU_all_call_sites
 DIE72: .uleb128 0x8    # (DIE (0x72) DW_TAG_formal_parameter)
-       .long   DIE39   # DW_AT_abstract_origin
+       .long   DIE39 - .Ldebug_info0   # DW_AT_abstract_origin
        .uleb128 0x1    # DW_AT_location
        .byte   0x55    # DW_OP_reg5
        .byte   0       # end of children of DIE 0x57
@@ -155,7 +155,7 @@ DIE7a:      .uleb128 0x9    # (DIE (0x7a) DW_TAG_subprogram)
        .long   .LASF3  # DW_AT_name: "main"
        .byte   0x1     # DW_AT_decl_file (gdb.arch/amd64-entry-value-paramref.cc)
        .byte   0x1d    # DW_AT_decl_line
-       .long   DIE45   # DW_AT_type
+       .long   DIE45 - .Ldebug_info0   # DW_AT_type
        .quad   .LFB1   # DW_AT_low_pc
        .quad   .LFE1-.LFB1     # DW_AT_high_pc
        .uleb128 0x1    # DW_AT_frame_base
@@ -168,13 +168,13 @@ DIEac:    .uleb128 0xb    # (DIE (0xac) DW_TAG_variable)
        .ascii "var\0"  # DW_AT_name
        .byte   0x1     # DW_AT_decl_file (gdb.arch/amd64-entry-value-paramref.cc)
        .byte   0x1f    # DW_AT_decl_line
-       .long   DIE45   # DW_AT_type
+       .long   DIE45 - .Ldebug_info0   # DW_AT_type
        .uleb128 0x2    # DW_AT_location
        .byte   0x91    # DW_OP_fbreg
        .sleb128 -12
 DIEba: .uleb128 0xc    # (DIE (0xba) DW_TAG_GNU_call_site)
        .quad   .LVL1   # DW_AT_low_pc
-       .long   DIE57   # DW_AT_abstract_origin
+       .long   DIE57 - .Ldebug_info0   # DW_AT_abstract_origin
 DIEc7: .uleb128 0xd    # (DIE (0xc7) DW_TAG_GNU_call_site_parameter)
        .uleb128 0x1    # DW_AT_location
        .byte   0x55    # DW_OP_reg5
@@ -200,25 +200,25 @@ DIEd2:    .uleb128 0xe    # (DIE (0xd2) DW_TAG_variable)
        .ascii "vv\0"   # DW_AT_name
        .byte   0x1     # DW_AT_decl_file (gdb.arch/amd64-entry-value-paramref.cc)
        .byte   0x12    # DW_AT_decl_line
-       .long   DIEe6   # DW_AT_type
+       .long   DIEe6 - .Ldebug_info0   # DW_AT_type
                        # DW_AT_external
        .uleb128 0x9    # DW_AT_location
        .byte   0x3     # DW_OP_addr
        .quad   vv
 DIEe6: .uleb128 0xf    # (DIE (0xe6) DW_TAG_volatile_type)
-       .long   DIE45   # DW_AT_type
+       .long   DIE45 - .Ldebug_info0   # DW_AT_type
 DIEeb: .uleb128 0xe    # (DIE (0xeb) DW_TAG_variable)
        .ascii "p\0"    # DW_AT_name
        .byte   0x1     # DW_AT_decl_file (gdb.arch/amd64-entry-value-paramref.cc)
        .byte   0x12    # DW_AT_decl_line
-       .long   DIEfe   # DW_AT_type
+       .long   DIEfe - .Ldebug_info0   # DW_AT_type
                        # DW_AT_external
        .uleb128 0x9    # DW_AT_location
        .byte   0x3     # DW_OP_addr
        .quad   p
 DIEfe: .uleb128 0x10   # (DIE (0xfe) DW_TAG_pointer_type)
        .byte   0x8     # DW_AT_byte_size
-       .long   DIEe6   # DW_AT_type
+       .long   DIEe6 - .Ldebug_info0   # DW_AT_type
        .byte   0       # end of children of DIE 0xb
 .Linfo_end:
        .section        .debug_abbrev,"",@progbits