From 93a360cc5d11a18572239b30d5bae63703012086 Mon Sep 17 00:00:00 2001 From: Omair Javaid Date: Thu, 16 Jan 2014 11:00:00 +0000 Subject: [PATCH] Fix testsuite/gdb.dwarf2/dw2-dos-drive.exp on ARM. This test currently fails on ARM: (gdb) PASS: gdb.dwarf2/dw2-dos-drive.exp: set breakpoint pending off break 'z:file.c':func Cannot access memory at address 0x0 The error is GDB trying to read the prologue at the breakpoint's address, and failing: 38 throw_error() exceptions.c:444 0x0016728c 37 memory_error() corefile.c:204 0x001d1fcc 36 read_memory() corefile.c:223 0x001d201a 35 read_memory_unsigned_integer() corefile.c:312 0x001d2166 34 arm_skip_prologue() arm-tdep.c:1452 0x00054270 static CORE_ADDR arm_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc) { ... for (skip_pc = pc; skip_pc < limit_pc; skip_pc += 4) { inst = read_memory_unsigned_integer (skip_pc, 4, byte_order_for_code); The test doesn't execute the compiled object's code, so GDB will try to read memory from the binary's sections. Instructions on ARM are 4-byte wide, and thus ARM's prologue scanner reads in 4-byte chunks. As the section 'func' is put at is only 1 byte long, and no other section is allocated contiguously: ... Sections: Idx Name Size VMA LMA File off Algn 0 .text 00000001 00000000 00000000 00000034 2**0 CONTENTS, ALLOC, LOAD, READONLY, CODE ... ... the exec target fails the read the 4 bytes. Fix this by increasing the function's size. gdb/testsuite/ChangeLog: 2014-01-16 Omair Javaid * gdb.dwarf2/dw2-dos-drive.S: Increase text section size to 4 bytes. --- gdb/testsuite/ChangeLog | 5 +++++ gdb/testsuite/gdb.dwarf2/dw2-dos-drive.S | 3 ++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index df8678e..4d2fe91 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2014-01-16 Omair Javaid + + * gdb.dwarf2/dw2-dos-drive.S: Increase text section size to 4 + bytes. + 2014-01-15 Maciej W. Rozycki * gdb.base/float.exp: Handle "aarch64*-*-*" targets. diff --git a/gdb/testsuite/gdb.dwarf2/dw2-dos-drive.S b/gdb/testsuite/gdb.dwarf2/dw2-dos-drive.S index 6e9d360..84006f7 100644 --- a/gdb/testsuite/gdb.dwarf2/dw2-dos-drive.S +++ b/gdb/testsuite/gdb.dwarf2/dw2-dos-drive.S @@ -15,7 +15,8 @@ .text pc_start: - .byte 0 + /* Enough space to fit at least one instruction. */ + .4byte 0 pc_end: .section .debug_info -- 2.7.4