Don't assume break/continue inside a TRY block works

In C++, this:

	try
	  {
	    break;
	  }
	catch (..)
	  {}

is invalid.  However, because our TRY/CATCH macros support it in C,
the C++ version of those macros support it too.  To catch such
assumptions, this adds a (disabled) hack that maps TRY/CATCH to raw
C++ try/catch.  Then it goes through all instances that building on
x86_64 GNU/Linux trips on, fixing them.

This isn't strictly necessary yet, but I think it's nicer to try to
keep the tree in a state where it's easier to eliminate the TRY/CATCH
macros.

gdb/ChangeLog:
2015-10-29  Pedro Alves  <palves@redhat.com>

	* dwarf2-frame-tailcall.c (dwarf2_tailcall_sniffer_first): Don't
	assume that "break" breaks out of a TRY/CATCH.
	* python/py-framefilter.c (py_print_single_arg): Don't assume
	"continue" breaks out of a TRY/CATCH.
	* python/py-value.c (valpy_binop_throw): New function, factored
	out from ...
	(valpy_binop): ... this.
	(valpy_richcompare_throw): New function, factored
	out from ...
	(valpy_richcompare): ... this.
	* solib.c (solib_read_symbols): Don't assume "break" breaks out
	of a TRY/CATCH.
	* common/common-exceptions.h [USE_RAW_CXX_TRY]
	<TRY/CATCH/END_CATCH>: Define as 1-1 wrappers around try/catch.

1 files changed, 9 insertions, 7 deletions

diff --git a/gdb/dwarf2-frame-tailcall.c b/gdb/dwarf2-frame-tailcall.c
index 952bc14233..613cc34b89 100644
--- a/gdb/dwarf2-frame-tailcall.c
+++ b/gdb/dwarf2-frame-tailcall.c
@@ -386,13 +386,15 @@ dwarf2_tailcall_sniffer_first (struct frame_info *this_frame,
       /* call_site_find_chain can throw an exception.  */
       chain = call_site_find_chain (prev_gdbarch, prev_pc, this_pc);
 
-      if (entry_cfa_sp_offsetp == NULL)
-	break;
-      sp_regnum = gdbarch_sp_regnum (prev_gdbarch);
-      if (sp_regnum == -1)
-	break;
-      prev_sp = frame_unwind_register_unsigned (this_frame, sp_regnum);
-      prev_sp_p = 1;
+      if (entry_cfa_sp_offsetp != NULL)
+	{
+	  sp_regnum = gdbarch_sp_regnum (prev_gdbarch);
+	  if (sp_regnum != -1)
+	    {
+	      prev_sp = frame_unwind_register_unsigned (this_frame, sp_regnum);
+	      prev_sp_p = 1;
+	    }
+	}
     }
   CATCH (except, RETURN_MASK_ERROR)
     {