Yao Qi [Tue, 25 Jul 2017 10:38:50 +0000 (11:38 +0100)]
Catch exceptions thrown from gdbarch_skip_prologue
PR 21555 is caused by the exception during the prologue analysis when re-set
a breakpoint.
(gdb) bt
#0 memory_error_message (err=TARGET_XFER_E_IO, gdbarch=0x153db50, memaddr=93824992233232) at ../../binutils-gdb/gdb/corefile.c:192
#1 0x00000000005718ed in memory_error (err=TARGET_XFER_E_IO, memaddr=memaddr@entry=93824992233232) at ../../binutils-gdb/gdb/corefile.c:220
#2 0x00000000005719d6 in read_memory_object (object=object@entry=TARGET_OBJECT_CODE_MEMORY, memaddr=93824992233232, memaddr@entry=1, myaddr=myaddr@entry=0x7fffffffd0a0 "P\333S\001", len=len@entry=1) at ../../binutils-gdb/gdb/corefile.c:259
#3 0x0000000000571c6e in read_code (len=1, myaddr=0x7fffffffd0a0 "P\333S\001", memaddr=<optimized out>) at ../../binutils-gdb/gdb/corefile.c:287
#4 read_code_unsigned_integer (memaddr=memaddr@entry=93824992233232, len=len@entry=1, byte_order=byte_order@entry=BFD_ENDIAN_LITTLE) at ../../binutils-gdb/gdb/corefile.c:362
#5 0x000000000041d4a0 in amd64_analyze_prologue (gdbarch=gdbarch@entry=0x153db50, pc=pc@entry=93824992233232, current_pc=current_pc@entry=18446744073709551615, cache=cache@entry=0x7fffffffd1e0) at ../../binutils-gdb/gdb/amd64-tdep.c:2310
#6 0x000000000041e404 in amd64_skip_prologue (gdbarch=0x153db50, start_pc=93824992233232) at ../../binutils-gdb/gdb/amd64-tdep.c:2459
#7 0x000000000067bfb0 in skip_prologue_sal (sal=sal@entry=0x7fffffffd4e0) at ../../binutils-gdb/gdb/symtab.c:3628
#8 0x000000000067c4d8 in find_function_start_sal (sym=sym@entry=0x1549960, funfirstline=1) at ../../binutils-gdb/gdb/symtab.c:3501
#9 0x000000000060999d in symbol_to_sal (result=result@entry=0x7fffffffd5f0, funfirstline=<optimized out>, sym=sym@entry=0x1549960) at ../../binutils-gdb/gdb/linespec.c:3860
....
#16 0x000000000054b733 in location_to_sals (b=b@entry=0x15792d0, location=0x157c230, search_pspace=search_pspace@entry=0x1148120, found=found@entry=0x7fffffffdc64) at ../../binutils-gdb/gdb/breakpoint.c:14211
#17 0x000000000054c1f5 in breakpoint_re_set_default (b=0x15792d0) at ../../binutils-gdb/gdb/breakpoint.c:14301
#18 0x00000000005412a9 in breakpoint_re_set_one (bint=bint@entry=0x15792d0) at ../../binutils-gdb/gdb/breakpoint.c:14412
This problem can be fixed by
- either each prologue analyzer doesn't throw exception,
- or catch the exception thrown from gdbarch_skip_prologue,
I choose the latter because the former needs to fix *every* prologue
analyzer to not throw exception.
This error can be reproduced by changing reread.exp. The test reread.exp
has already test that breakpoint can be reset correctly after the
executable is re-read. This patch extends this test by compiling test c
file with and without -fPIE.
(gdb) run ^M
The program being debugged has been started already.^M
Start it from the beginning? (y or n) y^M
x86_64/gdb/testsuite/outputs/gdb.base/reread/reread' has changed; re-reading symbols.
Error in re-setting breakpoint 1: Cannot access memory at address 0x555555554790^M
Error in re-setting breakpoint 2: Cannot access memory at address 0x555555554790^M
Starting program: /scratch/yao/gdb/build-git/x86_64/gdb/testsuite/outputs/gdb.base/reread/reread ^M
This is foo^M
[Inferior 1 (process 27720) exited normally]^M
(gdb) FAIL: gdb.base/reread.exp: opts= "-fPIE" "ldflags=-pie" : run to foo() second time (the program exited)
This patch doesn't re-indent the code, to keep the patch simple.
Yao Qi [Tue, 25 Jul 2017 09:15:25 +0000 (10:15 +0100)]
[ARM] Access FPSCR on vfpv2
GDB can fetch or store FPSCR on vfpv3, which has 32 VFP registers, but
fail to do so on vfpv2, which has 16 VFP registers. GDB code is incorrect
for vfpv2,
else if (tdep->vfp_register_count > 0
&& regno >= ARM_D0_REGNUM
&& regno <= ARM_D0_REGNUM + tdep->vfp_register_count)
while FPSCR register number is defined as ARM_D0_REGNUM + 32.
The code above uses "<=" rather than "<", in order to put FPSCR in the
range, but it is only correct when tdep->vfp_register_count is 32. On
vpfv2, it is 16, and FPSCR is out of the range, so fetch_vfp_regs or
store_vfp_regs are not called.
* common/common-utils.h (REPLACE_TO_STRING) [__MINGW32__]: Define
to 1 if std::to_string is not available.
(gdb::to_string) [REPLACE_TO_STRING]: Provide a replacement
implementation for std::string.
Yao Qi [Wed, 17 May 2017 13:22:04 +0000 (14:22 +0100)]
Add alias command to cmd_list_element
When we add alias command, we call add_alias_cmd and pass the alias name
and command name. This implicitly requires the command and its prefix
commands are already added to cmdlist. This may not be true, for example,
"inferior-tty" command is added to setlist, but setlist may not be added
to cmdlist (It depends on the order of related _initialize_XXX functions
called) so that we can't find "set inferior-tty" from cmdlist.
This patch fixes this problem by passing cmd_list_element of "inferior-tty"
to add_alias_cmd, so that cmd_list_element of "inferior-tty" doesn't have
to be reachable from cmdlist at that moment.