testsuite: Verify -fshort-enums and -fno-short-enums in pr33738.C

For some targets, like Cortex-M on arm-none-eabi, the -fshort-enums is
enabled by default. For these targets, the test case fails as
sizeof(Alpha) < sizeof(int).
To make the test case behave identical for targets that does enable
-fshort-enums and those that does not, add -fno-short-enums in the test
case and verify that the warning is not emitted. Then also create a copy
and run the test with -fshort-enums and verify that the warning is
emitted.

Regtested on x86_64-pc-linux-gnu and arm-none-eabi.

gcc/testsuite/ChangeLog:

	* g++.dg/warn/pr33738.C: Added -fno-short-enums.
	* g++.dg/warn/pr33738-2.C: Duplicate g++.dg/warn/pr33738.C with
	-fshort-enums and removed xfail.

Signed-off-by: Torbjörn SVENSSON <torbjorn.svensson@foss.st.com>

2 files changed, 29 insertions, 1 deletions

diff --git a/gcc/testsuite/g++.dg/warn/pr33738-2.C b/gcc/testsuite/g++.dg/warn/pr33738-2.C
new file mode 100644
index 0000000..84bbdae
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/pr33738-2.C
@@ -0,0 +1,27 @@
+// { dg-do run }
+// { dg-options "-O2 -Wtype-limits -fstrict-enums -fshort-enums" }
+extern void link_error (void);
+
+enum Alpha {
+ ZERO = 0, ONE, TWO, THREE
+};
+
+Alpha a2;
+
+int m1 = -1;
+int GetM1() {
+ return m1;
+}
+
+int main() {
+ a2 = static_cast<Alpha>(GetM1());
+ if (a2 == -1) {	// { dg-warning "always false due" } */
+    link_error ();
+ }
+ a2 = static_cast<Alpha>(GetM1());
+ if (-1 == a2) {	// { dg-warning "always false due" } */
+    link_error ();
+ }
+ return 0;
+}
+
diff --git a/gcc/testsuite/g++.dg/warn/pr33738.C b/gcc/testsuite/g++.dg/warn/pr33738.C
index 73e98d5..d899f91 100644
--- a/gcc/testsuite/g++.dg/warn/pr33738.C
+++ b/gcc/testsuite/g++.dg/warn/pr33738.C
@@ -1,5 +1,6 @@
 // { dg-do run }
-// { dg-options "-O2 -Wtype-limits -fstrict-enums" }
+// { dg-prune-output "use of enum values across objects may fail" }
+// { dg-options "-O2 -Wtype-limits -fstrict-enums -fno-short-enums" }
 extern void link_error (void);
 
 enum Alpha {