C++ compile support

This patch adds *basic* support for C++ to the compile feature.  It does
most simple type conversions, including everything that C compile does and
your basic "with-classes" type of C++.

I've written a new compile-support.exp support file which adds a new test
facility for automating and simplifying "compile print" vs "compile code"
testing.  See testsuite/lib/compile-support.exp and CompileExpression
for more on that.  The tests use this facility extensively.

This initial support has several glaring omissions:
- No template support at all
  I have follow-on patches for this, but they add much complexity
  to this "basic" support.  Consequently, they will be submitted separately.
- Cannot print functions
  The code template needs tweaking, and I simply haven't gotten to it yet.
- So-called "special function" support is not included
  Using constructors, destructors, operators, etc will not work. I have
  follow-on patches for that, but they require some work because of the
  recent churn in symbol searching.
- There are several test suite references to "compile/1234" bugs.
  I will file bugs and update the test suite's bug references before pushing
  these patches.

The test suite started as a copy of the original C-language support, but
I have written tests to exercise the basic functionality of the plug-in.

I've added a new option for outputting debug messages for C++ type-conversion
("debug compile-cplus-types").

gdb/ChangeLog:

	* Makefile.in (SUBDIR_GCC_COMPILE_SRCS): Add compile-cplus-symbols.c
	and compile-cplus-types.c.
	(HFILES_NO_SRCDIR): Add gcc-cp-plugin.h.
	* c-lang.c (cplus_language_defn): Set C++ compile functions.
	* c-lang.h (cplus_get_compile_context, cplus_compute_program):
	Declare.
	* compile/compile-c-support.c: Include compile-cplus.h.
	(load_libcompile): Templatize.
	(get_compile_context): "New" function.
	(c_get_compile_context): Use get_compile_context.
	(cplus_get_compile_context): New function.
	(cplus_push_user_expression, cplus_pop_user_expression)
	(cplus_add_code_header, cplus_add_input, cplus_compile_program)
	(cplus_compute_program): Define new structs/functions.
	* compile/compile-cplus-symmbols.c: New file.
	* compile/compile-cplus-types.c: New file.
	* compile/compile-cplus.h: New file.
	* compile/compile-internal.h (debug_compile_oracle, GCC_TYPE_NONE):
	Declare.
	* compile/compile-object-load.c (get_out_value_type): Use
	strncmp_iw when comparing symbol names.
	(compile_object_load): Add mst_bss and mst_data.
	* compile/compile.c (_initialize_compile): Remove
	-Wno-implicit-function-declaration from `compile_args'.
	* compile/gcc-cp-plugin.h: New file.
	* NEWS: Mention C++ compile support and new debug options.

gdb/testsuite/ChangeLog:

	* gdb.compile/compile-cplus-anonymous.cc: New file.
	* gdb.compile/compile-cplus-anonymous.exp: New file.
	* gdb.compile/compile-cplus-array-decay.cc: New file.
	* gdb.compile/compile-cplus-array-decay.exp: New file.
	* gdb.compile/compile-cplus-inherit.cc: New file.
	* gdb.compile/compile-cplus-inherit.exp: New file.
	* gdb.compile/compile-cplus-member.cc: New file.
	* gdb.compile/compile-cplus-member.exp: New file.
	* gdb.compile/compile-cplus-method.cc: New file.
	* gdb.compile/compile-cplus-method.exp: New file.
	* gdb.compile/compile-cplus-mod.c: "New" file.
	* gdb.compile/compile-cplus-namespace.cc: New file.
	* gdb.compile/compile-cplus-namespace.exp: New file.
	* gdb.compile/compile-cplus-nested.cc: New file.
	* gdb.compile/compile-cplus-nested.exp: New file.
	* gdb.compile/compile-cplus-print.c: "New" file.
	* gdb.compile/compile-cplus-print.exp: "New" file.
	* gdb.compile/compile-cplus-virtual.cc: New file.
	* gdb.compile/compile-cplus-virtual.exp: New file.
	* gdb.compile/compile-cplus.c: "New" file.
	* gdb.compile/compile-cplus.exp: "New" file.
	* lib/compile-support.exp: New file.

doc/ChangeLog:

	* gdb.texinfo (Compiling and injecting code in GDB): Document
	set/show "compile-oracle" and "compile-cplus-types" commands.

1 files changed, 79 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.compile/compile-cplus-print.exp b/gdb/testsuite/gdb.compile/compile-cplus-print.exp
new file mode 100644
index 0000000..5b84b14
--- /dev/null
+++ b/gdb/testsuite/gdb.compile/compile-cplus-print.exp
@@ -0,0 +1,79 @@
+# Copyright 2015-2018 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+load_lib compile-support.exp
+
+standard_testfile
+
+get_compiler_info
+set options {}
+if [test_compiler_info gcc*] {
+    lappend options additional_flags=-g3
+    lappend options additional_flags=-std=gnu++11
+    lappend options c++
+}
+
+set srcfilesoptions [list ${srcfile} ${options}]
+
+if { [eval build_executable_from_specs ${testfile}.exp $testfile {$options} ${srcfilesoptions}] } {
+    return -1
+}
+
+clean_restart ${testfile}
+
+if {[skip_compile_feature_tests]} {
+    untested "compile command not supported (could not find libcc1 shared library?)"
+    return -1
+}
+
+gdb_test_no_output "set language c++" \
+    "Set language to C++"
+
+if ![runto_main] {
+    return -1
+}
+
+gdb_test "compile print varint" " = 10"
+gdb_test "compile print vararray" " = \\{1, 2, 3, 4, 5\\}"
+
+setup_kfail compile/23586 *-*-*
+gdb_test "compile print main" " = \\{int \\(void\\)\\} 0x\[0-9a-f\]+"
+
+setup_kfail compile/23587 *-*-*
+set test "compile print *vararray@3"
+gdb_test_multiple $test $test {
+    -re " = \\{1, 2, 3\\}\r\n$gdb_prompt $" {
+	pass $test
+    }
+    -re "warning: .*All references to this method will be undefined\.\r\n" {
+	exp_continue
+    }
+}
+
+setup_kfail compile/23587 *-*-*
+set test "compile print *vararrayp@3"
+gdb_test_multiple $test $test {
+    -re " = \\{1, 2, 3\\}\r\n$gdb_prompt $" {
+	pass $test
+    }
+    -re "warning: .*All references to this method will be undefined\.\r\n" {
+	exp_continue
+    }
+}
+
+gdb_test "compile print/x 256" " = 0x100"
+gdb_test {print $} " = 256"
+
+gdb_test "compile print varobject" { = {field = 1}}