gdb/23712: Test case for multidictionary

This is a test derived from one of the reproducers in symtab/23010.
The DIE tree used here is typical of compilations with LTO, where an
artificial parent DIE of language C99 imports DIEs of other languages.

gdb/testsuite/ChangeLog:

	PR gdb/23712
	PR symtab/23010
	* gdb.dwarf2/multidictionary.exp: New file.

2 files changed, 163 insertions, 0 deletions

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index bb9e2b34559..b0dec0d9bf8 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2019-01-10  Keith Seitz  <keiths@redhat.com>
+
+	PR gdb/23712
+	PR symtab/23010
+	* gdb.dwarf2/multidictionary.exp: New file.
+
 2019-01-09  Simon Marchi  <simon.marchi@ericsson.com>
 
 	* gdb.cp/demangle.exp (test_gnu_style_demangling): Rename to...
diff --git a/gdb/testsuite/gdb.dwarf2/multidictionary.exp b/gdb/testsuite/gdb.dwarf2/multidictionary.exp
new file mode 100644
index 00000000000..5588ef21441
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/multidictionary.exp
@@ -0,0 +1,157 @@
+# Copyright 2019 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/>.
+
+# A test of multi-language dictionaries, a solution to symtab/23010 et al.
+
+load_lib dwarf.exp
+
+# This test can only be run on targets which support DWARF.
+if {![dwarf2_support]} {
+    return 0
+}
+
+standard_testfile main.c .S
+
+# Create the DWARF.  This is derived from the reproducer in the bug
+# mentioned above.  This DIE tree is typical of compilations wtih
+# LTO enabled.
+
+set asm_file [standard_output_file $srcfile2]
+Dwarf::assemble $asm_file {
+    declare_labels D45d9 D5079 D5080 D50a9 D50af D5ab2 D5ac2 D5ace D5acf
+    declare_labels D2135f D2216a D22171 D226c4 D226ca D244ca \
+	D245da D245e6
+    declare_labels D41c21 D42025 D42045 D42038 D42045 D420b5
+
+    cu {} {
+	D45d9: compile_unit {
+	    {language @DW_LANG_C_plus_plus}
+	    {name "SerialPortUtils.cpp"}
+	} {
+	    D5079: base_type {
+		{byte_size 1 sdata}
+		{encoding @DW_ATE_unsigned}
+		{name "char"}
+	    }
+
+	    D5080: const_type {
+		{type :$D5079}
+	    }
+
+	    D50a9: pointer_type {
+		{byte_size 4 sdata}
+		{type :$D5080}
+	    }
+
+	    D50af: const_type {
+		{type :$D50a9}
+	    }
+
+	    D5ab2: subprogram {
+		{external 1 flag}
+		{linkage_name "_Z18SerialSyncWriteStrPKc"}
+	    } {
+		D5ac2: formal_parameter {
+		    {name "msg"}
+		    {type :$D50af}
+		}
+		D5ace: lexical_block {} {
+		    D5acf: DW_TAG_variable {
+			{name "p"}
+			{type :$D50a9}
+		    }
+		}
+	    }
+	}
+    }
+
+    cu {} {
+	D2135f: compile_unit {
+	    {language @DW_LANG_C_plus_plus}
+	    {name "Main.cpp"}
+	} {
+	    D2216a: base_type {
+		{byte_size 1 sdata}
+		{encoding @DW_ATE_unsigned_char}
+		{name "char"}
+	    }
+
+	    D22171: const_type {
+		{type :$D2216a}
+	    }
+
+	    D226c4: pointer_type {
+		{byte_size 4 sdata}
+		{type :$D22171}
+	    }
+
+	    D226ca: const_type {
+		{type :$D226c4}
+	    }
+
+	    D245da: subprogram {
+		{name "PrintPanicMsg"}
+	    } {
+		D245e6: formal_parameter {
+		    {name "msg"}
+		    {type :$D226ca}
+		}
+	    }
+	}
+    }
+
+    cu {} {
+       D41c21: compile_unit {
+           {language @DW_LANG_C99}
+           {name "<artificial>"}
+       } {
+           D42025: subprogram {
+               {abstract_origin %$D245da}
+               {low_pc 0x80b60 addr}
+               {high_pc 0x6c data4}
+           } {
+	       D42038: formal_parameter {
+		   {abstract_origin %$D245e6}
+	       }
+
+	       D42045: inlined_subroutine {
+                   {abstract_origin %$D5ab2}
+                   {low_pc 0x8060 addr}
+                   {high_pc 0xc data4}
+               } {
+                   D420b5: formal_parameter {
+                       {abstract_origin %$D5ac2}
+                   }
+               }
+           }
+       }
+    }
+}
+
+# Build the test executable.
+if {[build_executable $testfile.exp $testfile [list $asm_file $srcfile] {}] \
+	== -1} {
+    return -1
+}
+
+# We force the DIEs above to be read in via "-readnow".
+gdb_spawn_with_cmdline_opts "-readnow"
+gdb_load $binfile
+
+# All we need to do is check whether GDB is alive.  Without
+# multidictionaries, it will either crash, assert, or throw an
+# internal_error.
+gdb_test "p 1" "= 1" "GDB is alive"
+