[patch] [gdb/testsuite] include a use of the definition of a type to cause clang to emit debug info

[David Blaikie <dblaikie@gmail.com>]

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Clang has an optimization that causes a the debug info to only include
the declaration of a type if the type is referenced but never used in
a context that requires a definition (eg: pointers are handed around
but never deferenced).

This patch introduces a variable to one test file to cause clang to
emit the full definition of the type as well as fixing up a related
typo in the test message of the associated expect file.

Like the difference between GCC and Clang in the emission of unused
static entities, I think this case is also a matter of degrees - both
GCC and Clang implement other similar optimizations* to the one
outlined here and the GDB test suite has managed to pass without
disabling those optimizations in GCC and I hope it's suitable to do
the same for Clang.

Though admittedly I don't have much of the context of the history of
the testsuite, its priorities/preferences when it comes to
distinguishing testing compiler behavior versus debugger behavior,
etc.

* the one I know of involves dynamic types: both GCC and Clang only
emit the debug info definition of such a type in any translation unit
that emits the key function. This means in many contexts where a full
definition is provided in the source only a declaration is provided in
the debug info.

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commit 1128f6fb45483d45668d09e0696f4a590334e0c4
Author: David Blaikie <dblaikie@gmail.com>
Date:   Sat Apr 12 23:27:19 2014 -0700

    Cause clang to emit the definition of a type used only by pointer
    
    gdb/testsuite/
    	* gdb.stabs/gdb11479.c: introduce a variable to cause clang to
    	emit the full definition of type required by the test
    	* gdb.stabs/gdb11479.exp: correct a typo in a test message

diff --git gdb/testsuite/ChangeLog gdb/testsuite/ChangeLog
index 730c116..07ba18e 100644
--- gdb/testsuite/ChangeLog
+++ gdb/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2014-04-12  David Blaikie  <dblaikie@gmail.com>
+
+        * gdb.stabs/gdb11479.c: introduce a variable to cause clang to
+	emit the full definition of type required by the test
+        * gdb.stabs/gdb11479.exp: correct a typo in a test message
+
 2014-04-12  Siva Chandra Reddy  <sivachandra@google.com>
 	    Doug Evans  <xdje42@gmail.com>
 
diff --git gdb/testsuite/gdb.stabs/gdb11479.c gdb/testsuite/gdb.stabs/gdb11479.c
index eb7fcf9..f70930f 100644
--- gdb/testsuite/gdb.stabs/gdb11479.c
+++ gdb/testsuite/gdb.stabs/gdb11479.c
@@ -55,7 +55,7 @@ struct dummy {
 enum dummy_enum {
   enum1,
   enum2
-};
+} tag_dummy_enum;
 
 void *
 hack (const struct dummy *t, const enum dummy_enum *e)
diff --git gdb/testsuite/gdb.stabs/gdb11479.exp gdb/testsuite/gdb.stabs/gdb11479.exp
index b9ed238..a2782ac 100644
--- gdb/testsuite/gdb.stabs/gdb11479.exp
+++ gdb/testsuite/gdb.stabs/gdb11479.exp
@@ -31,13 +31,13 @@ proc do_test {version} {
     gdb_test "print *t" ".*\{x = 5, y = 25, b = 2.5\}.*" \
 	"Inspect t in test2 $version"
     # Check that the enum type length has been set to a non-zero value
-    gdb_test "print sizeof (*e)" "= \[1-9\]*" "sizeof (e) in test2 $version"
+    gdb_test "print sizeof (*e)" "= \[1-9\]*" "sizeof (*e) in test2 $version"
     gdb_test "continue" "Breakpoint .* test .*" \
 	"Stop at first breakpoint $version"
     gdb_test "print *t" ".*\{x = 5, y = 25, b = 2.5\}.*" \
 	"Inspect t in test $version"
     # Check that the enum type length has been set to a non-zero value
-    gdb_test "print sizeof (*e)" "= \[1-9\]*" "sizeof (e) in test $version"
+    gdb_test "print sizeof (*e)" "= \[1-9\]*" "sizeof (*e) in test $version"
 }
 
 if { [prepare_for_testing $testfile.exp $testfile $testfile.c {debug additional_flags=-gstabs}] == 0 } {