default_read_var_value <LOC_UNRESOLVED>: Include minsym kind in error message.

bfd/ChangeLog:

	* targets.c (enum bfd_flavour): Add comment.
	(bfd_flavour_name): New function.
	* bfd-in2.h: Regenerate.

gdb/ChangeLog:

	* findvar.c (default_read_var_value) <LOC_UNRESOLVED>: Include the
	kind of minimal symbol in the error message.
	* objfiles.c (objfile_flavour_name): New function.
	* objfiles.h (objfile_flavour_name): Declare.

gdb/testsuite/ChangeLog:

	* gdb.dwarf2/dw2-bad-unresolved.c: New file.
	* gdb.dwarf2/dw2-bad-unresolved.exp: New file.

7 files changed, 123 insertions, 1 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 074417d..d0d35b0 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@
+2015-09-18  Doug Evans  <xdje42@gmail.com>
+
+	* findvar.c (default_read_var_value) <LOC_UNRESOLVED>: Include the
+	kind of minimal symbol in the error message.
+	* objfiles.c (objfile_flavour_name): New function.
+	* objfiles.h (objfile_flavour_name): Declare.
+
 2015-09-18  Yao Qi  <yao.qi@linaro.org>
 
 	* nat/aarch64-linux.c: Include elf/common.h,
diff --git a/gdb/findvar.c b/gdb/findvar.c
index fd1b9d7..11325cf 100644
--- a/gdb/findvar.c
+++ b/gdb/findvar.c
@@ -737,8 +737,20 @@ default_read_var_value (struct symbol *var, const struct block *var_block,
 	   symbol_objfile (var));
 	msym = lookup_data.result.minsym;
 
+	/* If we can't find the minsym there's a problem in the symbol info.
+	   The symbol exists in the debug info, but it's missing in the minsym
+	   table.  */
 	if (msym == NULL)
-	  error (_("No global symbol \"%s\"."), SYMBOL_LINKAGE_NAME (var));
+	  {
+	    const char *flavour_name
+	      = objfile_flavour_name (symbol_objfile (var));
+
+	    /* We can't get here unless we've opened the file, so flavour_name
+	       can't be NULL.  */
+	    gdb_assert (flavour_name != NULL);
+	    error (_("Missing %s symbol \"%s\"."),
+		   flavour_name, SYMBOL_LINKAGE_NAME (var));
+	  }
 	obj_section = MSYMBOL_OBJ_SECTION (lookup_data.result.objfile, msym);
 	/* Relocate address, unless there is no section or the variable is
 	   a TLS variable. */
diff --git a/gdb/objfiles.c b/gdb/objfiles.c
index 907126c..f6be91e 100644
--- a/gdb/objfiles.c
+++ b/gdb/objfiles.c
@@ -1614,6 +1614,16 @@ objfile_debug_name (const struct objfile *objfile)
   return lbasename (objfile->original_name);
 }
 
+/* See objfiles.h.  */
+
+const char *
+objfile_flavour_name (struct objfile *objfile)
+{
+  if (objfile->obfd != NULL)
+    return bfd_flavour_name (bfd_get_flavour (objfile->obfd));
+  return NULL;
+}
+
 /* Provide a prototype to silence -Wmissing-prototypes.  */
 extern initialize_file_ftype _initialize_objfiles;
 
diff --git a/gdb/objfiles.h b/gdb/objfiles.h
index be2a5ef..da5ac1a 100644
--- a/gdb/objfiles.h
+++ b/gdb/objfiles.h
@@ -744,6 +744,11 @@ const char *objfile_filename (const struct objfile *objfile);
 
 extern const char *objfile_debug_name (const struct objfile *objfile);
 
+/* Return the name of the file format of OBJFILE if the file has been opened,
+   otherwise return NULL.  */
+
+const char *objfile_flavour_name (struct objfile *objfile);
+
 /* Set the objfile's notion of the "main" name and language.  */
 
 extern void set_objfile_main_name (struct objfile *objfile,
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 53c32e8..e5fb03c 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-09-18  Doug Evans  <xdje42@gmail.com>
+
+	* gdb.dwarf2/dw2-bad-unresolved.c: New file.
+	* gdb.dwarf2/dw2-bad-unresolved.exp: New file.
+
 2015-09-18  Sandra Loosemore  <sandra@codesourcery.com>
 
 	* gdb.base/dso2dso.exp: Don't use directory prefix when setting
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-bad-unresolved.c b/gdb/testsuite/gdb.dwarf2/dw2-bad-unresolved.c
new file mode 100644
index 0000000..1c35510
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-bad-unresolved.c
@@ -0,0 +1,24 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2015 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/>.  */
+
+/* Dummy main function.  */
+
+int
+main (void)
+{
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-bad-unresolved.exp b/gdb/testsuite/gdb.dwarf2/dw2-bad-unresolved.exp
new file mode 100644
index 0000000..85c4ebb
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-bad-unresolved.exp
@@ -0,0 +1,59 @@
+# Copyright 2015 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 dwarf.exp
+
+# This test can only be run on targets which support DWARF-2 and use gas.
+if {![dwarf2_support]} {
+    return 0  
+}
+
+standard_testfile dw2-bad-unresolved.c dw2-bad-unresolved-2.S
+
+# Set up the DWARF for the test.
+# The key part of this is the definition of variable "var" having no location.
+# That will cause it to have LOC_UNRESOLVED.
+
+set asm_file [standard_output_file $srcfile2]
+Dwarf::assemble $asm_file {
+    cu {} {
+	DW_TAG_compile_unit {
+	    {DW_AT_language @DW_LANG_C}
+	    {DW_AT_name     dw2-bad-unresolved-2.c}
+	    {DW_AT_comp_dir /tmp}
+	} {
+	    declare_labels b_l
+
+	    b_l: DW_TAG_base_type {
+		{DW_AT_byte_size 1 DW_FORM_sdata}
+		{DW_AT_encoding  @DW_ATE_signed}
+		{DW_AT_name      bool}
+	    }
+	    DW_TAG_variable {
+		{name var}
+		{type :$b_l}
+		{external 1 flag}
+	    }
+	}
+    }
+}
+
+if { [prepare_for_testing ${testfile}.exp ${testfile} \
+	  [list $srcfile $asm_file] {nodebug}] } {
+    return -1
+}
+
+gdb_test "ptype var" "type = bool"
+gdb_test "print var" "Missing .* symbol \"var\"."