[RFA/commit] include alloca.h if available.

[RFA/commit] include alloca.h if available.

[Joel Brobecker]

On LynxOS, alloca is defined in allocal.h.  This fixes one warning that
occurs when building GDBserver for LynxOS.

gdb/gdbserver/ChangeLog:

        * configure.ac: Add configure check for alloca.
        * configure, config.in: Regenerate.
        * server.h: Include alloca.h if it exists.
        * gdbreplay.c: Include alloca.h if it exists.

Tested on x86_64-linux. No regression.

I think that's pretty straightforward, so I will commit in a couple of
days if there are no objections.

---
 gdb/gdbserver/config.in    |   23 +++++
 gdb/gdbserver/configure    |  191 ++++++++++++++++++++++++++++++++++++++++++++
 gdb/gdbserver/configure.ac |    1 +
 gdb/gdbserver/gdbreplay.c  |    4 +-
 gdb/gdbserver/server.h     |    4 +
 5 files changed, 222 insertions(+), 1 deletions(-)

diff --git a/gdb/gdbserver/config.in b/gdb/gdbserver/config.in
index c547776..a6a9704 100644
--- a/gdb/gdbserver/config.in
+++ b/gdb/gdbserver/config.in
@@ -1,5 +1,20 @@
 /* config.in.  Generated from configure.ac by autoheader.  */
 
+/* Define to one of `_getb67', `GETB67', `getb67' for Cray-2 and Cray-YMP
+   systems. This function is required for `alloca.c' support on those systems.
+   */
+#undef CRAY_STACKSEG_END
+
+/* Define to 1 if using `alloca.c'. */
+#undef C_ALLOCA
+
+/* Define to 1 if you have `alloca', as a function or macro. */
+#undef HAVE_ALLOCA
+
+/* Define to 1 if you have <alloca.h> and it should be used (not on Ultrix).
+   */
+#undef HAVE_ALLOCA_H
+
 /* Define to 1 if you have the <arpa/inet.h> header file. */
 #undef HAVE_ARPA_INET_H
 
@@ -184,6 +199,14 @@
 /* Bug reporting address */
 #undef REPORT_BUGS_TO
 
+/* If using the C implementation of alloca, define if you know the
+   direction of stack growth for your system; otherwise it will be
+   automatically deduced at runtime.
+	STACK_DIRECTION > 0 => grows toward higher addresses
+	STACK_DIRECTION < 0 => grows toward lower addresses
+	STACK_DIRECTION = 0 => direction of growth unknown */
+#undef STACK_DIRECTION
+
 /* Define to 1 if you have the ANSI C header files. */
 #undef STDC_HEADERS
 
diff --git a/gdb/gdbserver/configure b/gdb/gdbserver/configure
index 146e61b..05a4eba 100755
--- a/gdb/gdbserver/configure
+++ b/gdb/gdbserver/configure
@@ -606,6 +606,7 @@ WARN_CFLAGS
 ustinc
 ustlibs
 LIBOBJS
+ALLOCA
 INSTALL_DATA
 INSTALL_SCRIPT
 INSTALL_PROGRAM
@@ -3796,6 +3797,196 @@ $as_echo "#define STDC_HEADERS 1" >>confdefs.h
 fi
 
 
+# The Ultrix 4.2 mips builtin alloca declared by alloca.h only works
+# for constant arguments.  Useless!
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for working alloca.h" >&5
+$as_echo_n "checking for working alloca.h... " >&6; }
+if test "${ac_cv_working_alloca_h+set}" = set; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#include <alloca.h>
+int
+main ()
+{
+char *p = (char *) alloca (2 * sizeof (int));
+			  if (p) return 0;
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_working_alloca_h=yes
+else
+  ac_cv_working_alloca_h=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_working_alloca_h" >&5
+$as_echo "$ac_cv_working_alloca_h" >&6; }
+if test $ac_cv_working_alloca_h = yes; then
+
+$as_echo "#define HAVE_ALLOCA_H 1" >>confdefs.h
+
+fi
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for alloca" >&5
+$as_echo_n "checking for alloca... " >&6; }
+if test "${ac_cv_func_alloca_works+set}" = set; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#ifdef __GNUC__
+# define alloca __builtin_alloca
+#else
+# ifdef _MSC_VER
+#  include <malloc.h>
+#  define alloca _alloca
+# else
+#  ifdef HAVE_ALLOCA_H
+#   include <alloca.h>
+#  else
+#   ifdef _AIX
+ #pragma alloca
+#   else
+#    ifndef alloca /* predefined by HP cc +Olibcalls */
+char *alloca ();
+#    endif
+#   endif
+#  endif
+# endif
+#endif
+
+int
+main ()
+{
+char *p = (char *) alloca (1);
+				    if (p) return 0;
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_func_alloca_works=yes
+else
+  ac_cv_func_alloca_works=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_func_alloca_works" >&5
+$as_echo "$ac_cv_func_alloca_works" >&6; }
+
+if test $ac_cv_func_alloca_works = yes; then
+
+$as_echo "#define HAVE_ALLOCA 1" >>confdefs.h
+
+else
+  # The SVR3 libPW and SVR4 libucb both contain incompatible functions
+# that cause trouble.  Some versions do not even contain alloca or
+# contain a buggy version.  If you still want to use their alloca,
+# use ar to extract alloca.o from them instead of compiling alloca.c.
+
+ALLOCA=\${LIBOBJDIR}alloca.$ac_objext
+
+$as_echo "#define C_ALLOCA 1" >>confdefs.h
+
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether \`alloca.c' needs Cray hooks" >&5
+$as_echo_n "checking whether \`alloca.c' needs Cray hooks... " >&6; }
+if test "${ac_cv_os_cray+set}" = set; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#if defined CRAY && ! defined CRAY2
+webecray
+#else
+wenotbecray
+#endif
+
+_ACEOF
+if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
+  $EGREP "webecray" >/dev/null 2>&1; then :
+  ac_cv_os_cray=yes
+else
+  ac_cv_os_cray=no
+fi
+rm -f conftest*
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_os_cray" >&5
+$as_echo "$ac_cv_os_cray" >&6; }
+if test $ac_cv_os_cray = yes; then
+  for ac_func in _getb67 GETB67 getb67; do
+    as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
+ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
+eval as_val=\$$as_ac_var
+   if test "x$as_val" = x""yes; then :
+
+cat >>confdefs.h <<_ACEOF
+#define CRAY_STACKSEG_END $ac_func
+_ACEOF
+
+    break
+fi
+
+  done
+fi
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking stack direction for C alloca" >&5
+$as_echo_n "checking stack direction for C alloca... " >&6; }
+if test "${ac_cv_c_stack_direction+set}" = set; then :
+  $as_echo_n "(cached) " >&6
+else
+  if test "$cross_compiling" = yes; then :
+  ac_cv_c_stack_direction=0
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+$ac_includes_default
+int
+find_stack_direction ()
+{
+  static char *addr = 0;
+  auto char dummy;
+  if (addr == 0)
+    {
+      addr = &dummy;
+      return find_stack_direction ();
+    }
+  else
+    return (&dummy > addr) ? 1 : -1;
+}
+
+int
+main ()
+{
+  return find_stack_direction () < 0;
+}
+_ACEOF
+if ac_fn_c_try_run "$LINENO"; then :
+  ac_cv_c_stack_direction=1
+else
+  ac_cv_c_stack_direction=-1
+fi
+rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
+  conftest.$ac_objext conftest.beam conftest.$ac_ext
+fi
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_c_stack_direction" >&5
+$as_echo "$ac_cv_c_stack_direction" >&6; }
+cat >>confdefs.h <<_ACEOF
+#define STACK_DIRECTION $ac_cv_c_stack_direction
+_ACEOF
+
+
+fi
+
 for ac_header in sgtty.h termio.h termios.h sys/reg.h string.h 		 proc_service.h sys/procfs.h thread_db.h linux/elf.h 		 stdlib.h unistd.h 		 errno.h fcntl.h signal.h sys/file.h malloc.h 		 sys/ioctl.h netinet/in.h sys/socket.h netdb.h 		 netinet/tcp.h arpa/inet.h sys/wait.h
 do :
   as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
diff --git a/gdb/gdbserver/configure.ac b/gdb/gdbserver/configure.ac
index 33f29cf..bc3bb11 100644
--- a/gdb/gdbserver/configure.ac
+++ b/gdb/gdbserver/configure.ac
@@ -36,6 +36,7 @@ AC_ARG_PROGRAM
 
 AC_HEADER_STDC
 
+AC_FUNC_ALLOCA
 AC_CHECK_HEADERS(sgtty.h termio.h termios.h sys/reg.h string.h dnl
 		 proc_service.h sys/procfs.h thread_db.h linux/elf.h dnl
 		 stdlib.h unistd.h dnl
diff --git a/gdb/gdbserver/gdbreplay.c b/gdb/gdbserver/gdbreplay.c
index 44e325b..4996ffa 100644
--- a/gdb/gdbserver/gdbreplay.c
+++ b/gdb/gdbserver/gdbreplay.c
@@ -57,10 +57,12 @@
 #if HAVE_MALLOC_H
 #include <malloc.h>
 #endif
-
 #if USE_WIN32API
 #include <winsock2.h>
 #endif
+#if HAVE_ALLOCA_H
+#include <alloca.h>
+#endif
 
 #ifndef HAVE_SOCKLEN_T
 typedef int socklen_t;
diff --git a/gdb/gdbserver/server.h b/gdb/gdbserver/server.h
index d612b0d..b401960 100644
--- a/gdb/gdbserver/server.h
+++ b/gdb/gdbserver/server.h
@@ -38,6 +38,10 @@
 #include <string.h>
 #endif
 
+#ifdef HAVE_ALLOCA_H
+#include <alloca.h>
+#endif
+
 #if !HAVE_DECL_STRERROR
 #ifndef strerror
 extern char *strerror (int);	/* X3.159-1989  4.11.6.2 */
-- 
1.7.1

Re: [RFA/commit] include alloca.h if available.

[Pedro Alves]

On Tuesday 31 August 2010 20:05:11, Joel Brobecker wrote:
> On LynxOS, alloca is defined in allocal.h.  This fixes one warning that
> occurs when building GDBserver for LynxOS.

No objections here.  One note.

> gdb/gdbserver/ChangeLog:
> 
>         * configure.ac: Add configure check for alloca.
>         * configure, config.in: Regenerate.

>         * server.h: Include alloca.h if it exists.

Every include of malloc.h in gdbserver's common code:

$ grep malloc\\.h *.c
gdbreplay.c:#include <malloc.h>
mem-break.c:#include <malloc.h>
server.c:#include <malloc.h>
tracepoint.c:#include <malloc.h>
utils.c:#include <malloc.h>
win32-low.c:#include <malloc.h>

is there for alloca on mingw32.  It might have made
sense to keep those together.  I don't really care that
much either way, just pointing it out.  :-)

-- 
Pedro Alves

Re: [RFA/commit] include alloca.h if available.

[Joel Brobecker]

> > On LynxOS, alloca is defined in allocal.h.  This fixes one warning that
> > occurs when building GDBserver for LynxOS.
> 
> No objections here.  One note.

Cool - checked in.

> Every include of malloc.h in gdbserver's common code:
> 
> $ grep malloc\\.h *.c
> gdbreplay.c:#include <malloc.h>
> mem-break.c:#include <malloc.h>
> server.c:#include <malloc.h>
> tracepoint.c:#include <malloc.h>
> utils.c:#include <malloc.h>
> win32-low.c:#include <malloc.h>
> 
> is there for alloca on mingw32.  It might have made
> sense to keep those together.  I don't really care that
> much either way, just pointing it out.  :-)

If it is just for malloc, it sounds like the include is no longer
necessary? Unless of course malloc.h is the only location where
alloca is defined on mingw32. Either way, since I'm working in
that area of the code, might as well look at it - I think I'm
setup to build the gdbserver on MinGW.

-- 
Joel

Re: [RFA/commit] include alloca.h if available.

[Joel Brobecker]

> If it is just for malloc, it sounds like the include is no longer
> necessary? Unless of course malloc.h is the only location where
> alloca is defined on mingw32.

I just checked, and from what I can tell, no alloca.h on MinGW.
So the question is: Do we want to group all includes of malloc.h
in server.h? I don't see any strong reason to believe that one
way or the other is better, so I can live with the status quo.
But I'm happy to group them all, or even move the include of
alloca.h inside the various .c file as needed (it seems odd, now
that I think of it, to include alloca.h in server.h, and yet have
the includes of malloc.h spread out in the .c files).

-- 
Joel

Re: [RFA/commit] include alloca.h if available.

[Pedro Alves]

On Wednesday 01 September 2010 05:38:10, Joel Brobecker wrote:
> > If it is just for malloc, it sounds like the include is no longer
> > necessary? Unless of course malloc.h is the only location where
> > alloca is defined on mingw32.
> I just checked, and from what I can tell, no alloca.h on MinGW.

Right.  malloc.h is there for alloca, and there is no alloca.h, AFAIK.

> So the question is: Do we want to group all includes of malloc.h
> in server.h? I don't see any strong reason to believe that one
> way or the other is better, so I can live with the status quo.
> But I'm happy to group them all, or even move the include of
> alloca.h inside the various .c file as needed (it seems odd, now
> that I think of it, to include alloca.h in server.h, and yet have
> the includes of malloc.h spread out in the .c files).

This is exactly what I was pointing at.  It'd be tidier to have
alloca.h and malloc.h together, either in server.h or spread out
in the .c files, but together.  Just for the principle that
headers should only contain includes of what is scrictly necessary
for the interface they describe, I'd prefer the .c files.  But
then again, server.h is a kitchen sink, and, already includes
other related system includes like stdlib.h and string.h, that
putting it there is certainly fine, and probably avoids more work
in the future (note how I needed to add malloc.h to mem-break.c
recently for mingw32).  Thus, I mildly prefer server.h as you
have done.  But this was just a note, not a request!

-- 
Pedro Alves

[RFA/gdbserver] Move malloc.h include to server.h.

[Joel Brobecker]

As discussed:

This patch moves all includes of malloc.h, which were introduced
purely to get access to alloca's declaration, to server.h, next
to the include of alloca.h.

There is one exception: gdbreplay.c, which does not include server.h.
In this case, the include of alloca.h was simply moved up a bit, next
to the include of malloc.h.

gdb/gdbserver/ChangeLog:

        * gdbserver/gdbreplay.c: Move include of alloca.h up, next to
        include of malloc.h.
        * gdbserver/server.h: Add include of malloc.h.
        * gdbserver/mem-break.c: Remove include of malloc.h.
        * gdbserver/server.c, gdbserver/tracepoint.c, gdbserver/utils.c,
        gdbserver/win32-low.c: Likewise.

Tested on x86_64-linux. I also verified that gdbserver still builds
on MinGW...

---
 gdb/gdbserver/gdbreplay.c  |    6 +++---
 gdb/gdbserver/mem-break.c  |    3 ---
 gdb/gdbserver/server.c     |    3 ---
 gdb/gdbserver/server.h     |    5 +++++
 gdb/gdbserver/tracepoint.c |    3 ---
 gdb/gdbserver/utils.c      |    3 ---
 gdb/gdbserver/win32-low.c  |    1 -
 7 files changed, 8 insertions(+), 16 deletions(-)

diff --git a/gdb/gdbserver/gdbreplay.c b/gdb/gdbserver/gdbreplay.c
index 4996ffa..1f65111 100644
--- a/gdb/gdbserver/gdbreplay.c
+++ b/gdb/gdbserver/gdbreplay.c
@@ -54,15 +54,15 @@
 #if HAVE_NETINET_TCP_H
 #include <netinet/tcp.h>
 #endif
+#if HAVE_ALLOCA_H
+#include <alloca.h>
+#endif
 #if HAVE_MALLOC_H
 #include <malloc.h>
 #endif
 #if USE_WIN32API
 #include <winsock2.h>
 #endif
-#if HAVE_ALLOCA_H
-#include <alloca.h>
-#endif
 
 #ifndef HAVE_SOCKLEN_T
 typedef int socklen_t;
diff --git a/gdb/gdbserver/mem-break.c b/gdb/gdbserver/mem-break.c
index 687414b..1b08415 100644
--- a/gdb/gdbserver/mem-break.c
+++ b/gdb/gdbserver/mem-break.c
@@ -20,9 +20,6 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include "server.h"
-#if HAVE_MALLOC_H
-#include <malloc.h>
-#endif
 
 const unsigned char *breakpoint_data;
 int breakpoint_len;
diff --git a/gdb/gdbserver/server.c b/gdb/gdbserver/server.c
index c406abe..528b658 100644
--- a/gdb/gdbserver/server.c
+++ b/gdb/gdbserver/server.c
@@ -28,9 +28,6 @@
 #if HAVE_SYS_WAIT_H
 #include <sys/wait.h>
 #endif
-#if HAVE_MALLOC_H
-#include <malloc.h>
-#endif
 
 ptid_t cont_thread;
 ptid_t general_thread;
diff --git a/gdb/gdbserver/server.h b/gdb/gdbserver/server.h
index 286c80a..d5f32e8 100644
--- a/gdb/gdbserver/server.h
+++ b/gdb/gdbserver/server.h
@@ -41,6 +41,11 @@
 #ifdef HAVE_ALLOCA_H
 #include <alloca.h>
 #endif
+/* On some systems such as MinGW, alloca is declared in malloc.h
+   (there is no alloca.h).  */
+#if HAVE_MALLOC_H
+#include <malloc.h>
+#endif
 
 #if !HAVE_DECL_STRERROR
 #ifndef strerror
diff --git a/gdb/gdbserver/tracepoint.c b/gdb/gdbserver/tracepoint.c
index f068ce4..138d920 100644
--- a/gdb/gdbserver/tracepoint.c
+++ b/gdb/gdbserver/tracepoint.c
@@ -22,9 +22,6 @@
 #include <unistd.h>
 #include <sys/time.h>
 #include <stddef.h>
-#if HAVE_MALLOC_H
-#include <malloc.h>
-#endif
 #if HAVE_STDINT_H
 #include <stdint.h>
 #endif
diff --git a/gdb/gdbserver/utils.c b/gdb/gdbserver/utils.c
index 7de086c..aee7e96 100644
--- a/gdb/gdbserver/utils.c
+++ b/gdb/gdbserver/utils.c
@@ -24,9 +24,6 @@
 #if HAVE_ERRNO_H
 #include <errno.h>
 #endif
-#if HAVE_MALLOC_H
-#include <malloc.h>
-#endif
 
 #ifdef IN_PROCESS_AGENT
 #  define PREFIX "ipa: "
diff --git a/gdb/gdbserver/win32-low.c b/gdb/gdbserver/win32-low.c
index dd26d73..5aea8b9 100644
--- a/gdb/gdbserver/win32-low.c
+++ b/gdb/gdbserver/win32-low.c
@@ -31,7 +31,6 @@
 #include <tlhelp32.h>
 #include <psapi.h>
 #include <sys/param.h>
-#include <malloc.h>
 #include <process.h>
 
 #ifndef USE_WIN32API
-- 
1.7.1

Re: [RFA/gdbserver] Move malloc.h include to server.h.

[Pedro Alves]

On Wednesday 01 September 2010 18:09:45, Joel Brobecker wrote:

> gdb/gdbserver/ChangeLog:
> 
>         * gdbserver/gdbreplay.c: Move include of alloca.h up, next to
>         include of malloc.h.
>         * gdbserver/server.h: Add include of malloc.h.
>         * gdbserver/mem-break.c: Remove include of malloc.h.
>         * gdbserver/server.c, gdbserver/tracepoint.c, gdbserver/utils.c,
>         gdbserver/win32-low.c: Likewise.
> 
> Tested on x86_64-linux. I also verified that gdbserver still builds
> on MinGW...

Awesome, thanks.  :-)  Please apply.

-- 
Pedro Alves

Re: [RFA/gdbserver] Move malloc.h include to server.h.

[Joel Brobecker]

> > gdb/gdbserver/ChangeLog:
> > 
> >         * gdbserver/gdbreplay.c: Move include of alloca.h up, next to
> >         include of malloc.h.
> >         * gdbserver/server.h: Add include of malloc.h.
> >         * gdbserver/mem-break.c: Remove include of malloc.h.
> >         * gdbserver/server.c, gdbserver/tracepoint.c, gdbserver/utils.c,
> >         gdbserver/win32-low.c: Likewise.
> > 
> > Tested on x86_64-linux. I also verified that gdbserver still builds
> > on MinGW...
> 
> Awesome, thanks.  :-)  Please apply.

Now applied (BTW: I removed the extraneous gdbserver/ in the ChangeLog
entry).

-- 
Joel