From: Alexandre Oliva <oliva@adacore.com>
Date: Mon, 20 Nov 2023 08:14:31 +0000 (-0300)
Subject: testsuite: analyzer: expect alignment warning with -fshort-enums
X-Git-Tag: basepoints/gcc-15~4530
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0e0e3420dfe1d302145b4eb3bbf311a4f39eeced;p=thirdparty%2Fgcc.git

testsuite: analyzer: expect alignment warning with -fshort-enums

On targets that have -fshort-enums enabled by default, the type casts
in the pr108251 analyzer tests warn that the byte-aligned enums may
not be sufficiently aligned to be a struct connection *.  The function
can't know better, the warning is reasonable, the code doesn't
expected enums to be shorter and less aligned than the struct.

Rather than use -fno-short-enums, I decided to embrace the warning on
targets that have short_enums enabled by default.

However, C++ doesn't issue the warning, because even with
-fshort-enums, enumeration types are not TYPE_PACKED, and the
expression is not sufficiently simplified by the C++ front-end for
check_and_warn_address_or_pointer_of_packed_member to identify the
insufficiently aligned pointer.  So don't expect the warning there.


for  gcc/testsuite/ChangeLog

	* c-c++-common/analyzer/null-deref-pr108251-smp_fetch_ssl_fc_has_early-O2.c:
	Expect "unaligned pointer value" warning on short_enums
	targets, but not in c++.
	* c-c++-common/analyzer/null-deref-pr108251-smp_fetch_ssl_fc_has_early.c:
	Likewise.
---

diff --git a/gcc/testsuite/c-c++-common/analyzer/null-deref-pr108251-smp_fetch_ssl_fc_has_early-O2.c b/gcc/testsuite/c-c++-common/analyzer/null-deref-pr108251-smp_fetch_ssl_fc_has_early-O2.c
index c46ffe91a6b4..aaa2031b6dca 100644
--- a/gcc/testsuite/c-c++-common/analyzer/null-deref-pr108251-smp_fetch_ssl_fc_has_early-O2.c
+++ b/gcc/testsuite/c-c++-common/analyzer/null-deref-pr108251-smp_fetch_ssl_fc_has_early-O2.c
@@ -61,7 +61,7 @@ static inline enum obj_type obj_type(const enum obj_type *t)
 }
 static inline struct connection *__objt_conn(enum obj_type *t)
 {
- return ((struct connection *)(((char *)(t)) - ((long)&((struct connection *)0)->obj_type)));
+ return ((struct connection *)(((char *)(t)) - ((long)&((struct connection *)0)->obj_type))); /* { dg-warning "unaligned pointer value" "warning" { target { short_enums && { ! c++ } } } } */
 }
 static inline struct connection *objt_conn(enum obj_type *t)
 {
diff --git a/gcc/testsuite/c-c++-common/analyzer/null-deref-pr108251-smp_fetch_ssl_fc_has_early.c b/gcc/testsuite/c-c++-common/analyzer/null-deref-pr108251-smp_fetch_ssl_fc_has_early.c
index ef34a76c50d6..6c96f5a76ef1 100644
--- a/gcc/testsuite/c-c++-common/analyzer/null-deref-pr108251-smp_fetch_ssl_fc_has_early.c
+++ b/gcc/testsuite/c-c++-common/analyzer/null-deref-pr108251-smp_fetch_ssl_fc_has_early.c
@@ -60,7 +60,7 @@ static inline enum obj_type obj_type(const enum obj_type *t)
 }
 static inline struct connection *__objt_conn(enum obj_type *t)
 {
- return ((struct connection *)(((char *)(t)) - ((long)&((struct connection *)0)->obj_type)));
+ return ((struct connection *)(((char *)(t)) - ((long)&((struct connection *)0)->obj_type))); /* { dg-warning "unaligned pointer value" "warning" { target { short_enums && { ! c++ } } } } */
 }
 static inline struct connection *objt_conn(enum obj_type *t)
 {