[patch] Fix unused static symbols so they're not dropped by clang

David Blaikie
2014-04-11T06:51:56Z

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Several tests used file-static functions and variables that were not
referenced by the code. Even at -O0, clang omits these entities at the
frontend so the tests fail.

Since it doesn't look like these tests needed this functionality for
what they were testing, I've modified the variables/functions to
either be non-static, or marked them with __attribute__((used)).

If it's preferred that I use the attribute more pervasively, rather
than just making the entities non-static, I can provide a patch for
that (or some other preferred solution). There's certainly precedent
for both (non-static entities and __attribute__((used)) in the
testsuite already and much more of the former than the latter).

I have commit-after-review access, so just looking for sign-off here.

Thanks,
- David

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commit d72b042cbd4f0af6d2e4ac6901445677b93f77ee
Author: David Blaikie <dblaikie@gmail.com>
Date: Thu Apr 10 23:45:28 2014 -0700

Ensure unreferenced static symbols aren't omitted by clang (either marking them __attribute__((used)) or making them non-static)

gdb/testsuite/
* gdb.base/catch-syscall.c: Make unreferenced statics non-static to
ensure clang would not discard them.
* gdb.base/gdbvars.c: Ditto.
* gdb.base/memattr.c: Ditto.
* gdb.base/whatis.c: Ditto.
* gdb.python/py-prettyprint.c: Ditto.
* gdb.trace/actions.c: Ditto.
* gdb.cp/ptype-cv-cp.cc: Mark unused global const int as used to
ensure clang would not discard it.

diff --git gdb/testsuite/ChangeLog gdb/testsuite/ChangeLog
index 12ed4f9..623831a 100644
--- gdb/testsuite/ChangeLog
+++ gdb/testsuite/ChangeLog
@@ -1,3 +1,15 @@
+2014-04-10 David Blaikie <dblaikie@gmail.com>
+
+ * gdb.base/catch-syscall.c: Make unreferenced statics non-static to
+ ensure clang would not discard them.
+ * gdb.base/gdbvars.c: Ditto.
+ * gdb.base/memattr.c: Ditto.
+ * gdb.base/whatis.c: Ditto.
+ * gdb.python/py-prettyprint.c: Ditto.
+ * gdb.trace/actions.c: Ditto.
+ * gdb.cp/ptype-cv-cp.cc: Mark unused global const int as used to
+ ensure clang would not discard it.
+
2014-04-10 Pedro Alves <palves@redhat.com>

* gdb.base/cond-eval-mode.c: New file.
diff --git gdb/testsuite/gdb.base/catch-syscall.c gdb/testsuite/gdb.base/catch-syscall.c
index aa5727a..ea33b93 100644
--- gdb/testsuite/gdb.base/catch-syscall.c
+++ gdb/testsuite/gdb.base/catch-syscall.c
@@ -14,16 +14,16 @@

/* These are the syscalls numbers used by the test. */

-static int close_syscall = SYS_close;
-static int chroot_syscall = SYS_chroot;
+int close_syscall = SYS_close;
+int chroot_syscall = SYS_chroot;
/* GDB had a bug where it couldn't catch syscall number 0 (PR 16297).
In most GNU/Linux architectures, syscall number 0 is
restart_syscall, which can't be called from userspace. However,
the "read" syscall is zero on x86_64. */
-static int read_syscall = SYS_read;
-static int pipe_syscall = SYS_pipe;
-static int write_syscall = SYS_write;
-static int exit_group_syscall = SYS_exit_group;
+int read_syscall = SYS_read;
+int pipe_syscall = SYS_pipe;
+int write_syscall = SYS_write;
+int exit_group_syscall = SYS_exit_group;

int
main (void)
diff --git gdb/testsuite/gdb.base/gdbvars.c gdb/testsuite/gdb.base/gdbvars.c
index 352a76b..46fa84b 100644
--- gdb/testsuite/gdb.base/gdbvars.c
+++ gdb/testsuite/gdb.base/gdbvars.c
@@ -4,12 +4,12 @@ typedef void *ptr;

ptr p = &p;

-static void
+void
foo_void (void)
{
}

-static int
+int
foo_int (void)
{
return 0;
diff --git gdb/testsuite/gdb.base/memattr.c gdb/testsuite/gdb.base/memattr.c
index 74b2d61..62868b6 100644
--- gdb/testsuite/gdb.base/memattr.c
+++ gdb/testsuite/gdb.base/memattr.c
@@ -16,11 +16,11 @@
along with this program. If not, see <http://www.gnu.org/licenses/>. */

#define MEMSIZE 64
-static int mem1[MEMSIZE] = {111, 222, 333, 444, 555};
-static int mem2[MEMSIZE];
-static int mem3[MEMSIZE];
-static int mem4[MEMSIZE];
-static int mem5[MEMSIZE];
+int mem1[MEMSIZE] = {111, 222, 333, 444, 555};
+int mem2[MEMSIZE];
+int mem3[MEMSIZE];
+int mem4[MEMSIZE];
+int mem5[MEMSIZE];

int main()
{
diff --git gdb/testsuite/gdb.base/whatis.c gdb/testsuite/gdb.base/whatis.c
index a1a3188..bcda5fd 100644
--- gdb/testsuite/gdb.base/whatis.c
+++ gdb/testsuite/gdb.base/whatis.c
@@ -88,14 +88,14 @@ double v_double_array[2];
a special case kludge in GDB (Unix system include files like to define
caddr_t), but for a variety of types. */
typedef char *char_addr;
-static char_addr a_char_addr;
+char_addr a_char_addr;
typedef unsigned short *ushort_addr;
-static ushort_addr a_ushort_addr;
+ushort_addr a_ushort_addr;
typedef signed long *slong_addr;
-static slong_addr a_slong_addr;
+slong_addr a_slong_addr;
#ifndef NO_LONG_LONG
typedef signed long long *slong_long_addr;
-static slong_long_addr a_slong_long_addr;
+slong_long_addr a_slong_long_addr;
#endif

char *v_char_pointer;
diff --git gdb/testsuite/gdb.cp/ptype-cv-cp.cc gdb/testsuite/gdb.cp/ptype-cv-cp.cc
index 6546f68..add4021 100644
--- gdb/testsuite/gdb.cp/ptype-cv-cp.cc
+++ gdb/testsuite/gdb.cp/ptype-cv-cp.cc
@@ -22,7 +22,7 @@ typedef volatile const_my_int volatile_const_my_int;
typedef const volatile_my_int const_volatile_my_int;

my_int v_my_int (0);
-const_my_int v_const_my_int (1);
+__attribute__((used)) const_my_int v_const_my_int (1);
volatile_my_int v_volatile_my_int (2);
const_volatile_my_int v_const_volatile_my_int (3);
volatile_const_my_int v_volatile_const_my_int (4);
diff --git gdb/testsuite/gdb.python/py-prettyprint.c gdb/testsuite/gdb.python/py-prettyprint.c
index 0fd05f5..817bf33 100644
--- gdb/testsuite/gdb.python/py-prettyprint.c
+++ gdb/testsuite/gdb.python/py-prettyprint.c
@@ -230,7 +230,7 @@ struct nullstr
struct string_repr string_1 = { { "one" } };
struct string_repr string_2 = { { "two" } };

-static int
+int
eval_func (int p1, int p2, int p3, int p4, int p5, int p6, int p7, int p8)
{
return p1;
diff --git gdb/testsuite/gdb.trace/actions.c gdb/testsuite/gdb.trace/actions.c
index 04c69f2..497d04d 100644
--- gdb/testsuite/gdb.trace/actions.c
+++ gdb/testsuite/gdb.trace/actions.c
@@ -116,7 +116,7 @@ unsigned long gdb_c_test( unsigned long *parm )
return ( (unsigned long) 0 );
}

-static void gdb_asm_test (void)
+void gdb_asm_test (void)
{
}