libbacktrace: declare getpagesize if necessary

libbacktrace/
	PR libbacktrace/95012
	* configure.ac: Check for getpagesize declaration.
	* mmap.c: Declare getpagesize if necessary.
	* mmapio.c: Likewise.

libbacktrace/ChangeLog

@@ -1,3 +1,13 @@
+2020-05-11  Ian Lance Taylor  <iant@golang.org>
+
+	PR libbacktrace/95012
+	* configure.ac: Check for getpagesize declaration.
+	* mmap.c: Declare getpagesize if necessary.
+	* mmapio.c: Likewise.
+	* configure: Regenerate.
+	* config.h.in: Regenerate.
+	* Makefile.in: Regenerate.
+
 2020-05-09  Roland McGrath  <mcgrathr@google.com>
 
 	* elf.c (elf_add): Bail early if there are no section headers at all.

libbacktrace/Makefile.in

@@ -2266,7 +2266,7 @@ uninstall-am:
 
 
 @HAVE_DSYMUTIL_TRUE@%.dSYM: %
-@HAVE_DSYMUTIL_TRUE@	$(DSYMUTIL) %<
+@HAVE_DSYMUTIL_TRUE@	$(DSYMUTIL) $<
 
 @HAVE_ELF_TRUE@@HAVE_OBJCOPY_DEBUGLINK_TRUE@@NATIVE_TRUE@elf_for_test.c: elf.c
 @HAVE_ELF_TRUE@@HAVE_OBJCOPY_DEBUGLINK_TRUE@@NATIVE_TRUE@	SEARCH='^#define SYSTEM_BUILD_ID_DIR.*$$'; \

libbacktrace/config.h.in

@@ -12,6 +12,10 @@
 /* Define to 1 if you have the `clock_gettime' function. */
 #undef HAVE_CLOCK_GETTIME
 
+/* Define to 1 if you have the declaration of `getpagesize', and to 0 if you
+   don't. */
+#undef HAVE_DECL_GETPAGESIZE
+
 /* Define to 1 if you have the declaration of `strnlen', and to 0 if you
    don't. */
 #undef HAVE_DECL_STRNLEN

libbacktrace/configure

@@ -13166,6 +13166,16 @@ fi
 cat >>confdefs.h <<_ACEOF
 #define HAVE_DECL_STRNLEN $ac_have_decl
 _ACEOF
+ac_fn_c_check_decl "$LINENO" "getpagesize" "ac_cv_have_decl_getpagesize" "$ac_includes_default"
+if test "x$ac_cv_have_decl_getpagesize" = xyes; then :
+  ac_have_decl=1
+else
+  ac_have_decl=0
+fi
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_DECL_GETPAGESIZE $ac_have_decl
+_ACEOF
 
 for ac_func in lstat readlink
 do :

libbacktrace/configure.ac

@@ -376,7 +376,7 @@ if test "$have_fcntl" = "yes"; then
 	    [Define to 1 if you have the fcntl function])
 fi
 
-AC_CHECK_DECLS(strnlen)
+AC_CHECK_DECLS([strnlen, getpagesize])
 AC_CHECK_FUNCS(lstat readlink)
 
 # Check for getexecname function.

libbacktrace/mmap.c

@@ -42,6 +42,10 @@ POSSIBILITY OF SUCH DAMAGE.  */
 #include "backtrace.h"
 #include "internal.h"
 
+#ifndef HAVE_DECL_GETPAGESIZE
+extern int getpagesize (void);
+#endif
+
 /* Memory allocation on systems that provide anonymous mmap.  This
    permits the backtrace functions to be invoked from a signal
    handler, assuming that mmap is async-signal safe.  */

libbacktrace/mmapio.c

@@ -40,6 +40,10 @@ POSSIBILITY OF SUCH DAMAGE.  */
 #include "backtrace.h"
 #include "internal.h"
 
+#ifndef HAVE_DECL_GETPAGESIZE
+extern int getpagesize (void);
+#endif
+
 #ifndef MAP_FAILED
 #define MAP_FAILED ((void *)-1)
 #endif