binutils-gdb/gdb/nat
Tom Tromey 7ae6857316 Fix regression on Windows with WOW64
Internally at AdaCore, we recently started testing a 64-bit gdb
debugging 32-bit processes.  This failed with gdb head, but not with
gdb 11.

The tests fail like this:

     Starting program: [...].exe
     warning: Could not load shared library symbols for WOW64_IMAGE_SECTION.
     Do you need "set solib-search-path" or "set sysroot"?
     warning: Could not load shared library symbols for WOW64_IMAGE_SECTION.
     Do you need "set solib-search-path" or "set sysroot"?
     warning: Could not load shared library symbols for NOT_AN_IMAGE.
     Do you need "set solib-search-path" or "set sysroot"?
     warning: Could not load shared library symbols for NOT_AN_IMAGE.
     Do you need "set solib-search-path" or "set sysroot"?

After some debugging and bisecting, to my surprise the bug was
introduced by commit 183be222 ("gdb, gdbserver: make target_waitstatus
safe").

The problem occurs in handle_exception.  Previously the code did:

    -  ourstatus->kind = TARGET_WAITKIND_STOPPED;
    [...]
	 case EXCEPTION_BREAKPOINT:
    [...]
    -	  ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
    [...]
	   /* FALLTHROUGH */
	 case STATUS_WX86_BREAKPOINT:
	   DEBUG_EXCEPTION_SIMPLE ("EXCEPTION_BREAKPOINT");
    -      ourstatus->value.sig = GDB_SIGNAL_TRAP;
    [...]
    -  last_sig = ourstatus->value.sig;

However, in the new code, the fallthrough case does:

    +      ourstatus->set_stopped (GDB_SIGNAL_TRAP);

... which changes the 'kind' in 'ourstatus' after falling through.

This patch rearranges the 'last_sig' setting to more closely match
what was done before (this is probably not strictly needed but also
seemed harmless), and removes the fall-through in the
'ignore_first_breakpoint' case when __x86_64__ is defined.
2022-04-14 09:56:26 -06:00
..
aarch64-hw-point.c
aarch64-hw-point.h
aarch64-linux-hw-point.c
aarch64-linux-hw-point.h
aarch64-linux.c
aarch64-linux.h
aarch64-mte-linux-ptrace.c
aarch64-mte-linux-ptrace.h
aarch64-sve-linux-ptrace.c
aarch64-sve-linux-ptrace.h
aarch64-sve-linux-sigcontext.h
amd64-linux-siginfo.c
amd64-linux-siginfo.h
fork-inferior.c
fork-inferior.h
gdb_ptrace.h
gdb_thread_db.h
glibc_thread_db.h
linux-btrace.c
linux-btrace.h
linux-namespaces.c
linux-namespaces.h
linux-nat.h
linux-osdata.c
linux-osdata.h
linux-personality.c
linux-personality.h
linux-procfs.c
linux-procfs.h
linux-ptrace.c
linux-ptrace.h
linux-waitpid.c
linux-waitpid.h
mips-linux-watch.c
mips-linux-watch.h
netbsd-nat.c
netbsd-nat.h
ppc-linux.c
ppc-linux.h
riscv-linux-tdesc.c
riscv-linux-tdesc.h
windows-nat.c
windows-nat.h
x86-cpuid.h
x86-dregs.c
x86-dregs.h
x86-gcc-cpuid.h
x86-linux-dregs.c
x86-linux-dregs.h
x86-linux.c
x86-linux.h