Build fixes for z/OS

Author: NWilson

configure.ac

@@ -72,6 +72,9 @@ m4_ifdef([AM_PROG_AR], [AM_PROG_AR])
 # Check for a 64-bit integer type
 AC_TYPE_INT64_T
 
+# Check for xlc which has some special (broken/non-standard) behaviour on z/OS.
+PCRE2_ZOS_FIXES
+
 AC_PROG_INSTALL
 LT_INIT([win32-dll])
 AC_PROG_LN_S

m4/pcre2_zos.m4

@@ -0,0 +1,50 @@
+dnl Tests whether the compiler requires an additional flag in order to fail on
+dnl undefined headers.
+
+dnl The concept of setting this commandline flag was learned from patches and
+dnl mailing list discussions of the gnulib and gawk projects (credit to
+dnl Bruno Haible).
+
+AC_DEFUN([PCRE2_ZOS_FIXES],
+[
+  AC_CACHE_CHECK([for OS/390 (z/OS)], [pcre2_cv_os390],
+    [if test "`uname`" = "OS/390"; then
+       pcre2_cv_os390=yes
+     else
+       pcre2_cv_os390=no
+     fi])
+  if test "$pcre2_cv_os390" = "yes"; then
+    AC_CACHE_CHECK([whether the compiler supports -qhaltonmsg=CCN3296], [pcre2_cv_xlc_qhaltonmsg_support],
+      [save_CFLAGS="$CFLAGS"
+      CFLAGS="$CFLAGS -qhaltonmsg=CCN3296"
+      AC_COMPILE_IFELSE([AC_LANG_PROGRAM([])],
+                        [pcre2_cv_xlc_qhaltonmsg_support=yes],
+                        [pcre2_cv_xlc_qhaltonmsg_support=no])
+      CFLAGS="$save_CFLAGS"
+      ])
+
+    AC_CACHE_CHECK([whether non-existent headers fail the compile], [pcre2_cv_xlc_nonexistent_fatal],
+      [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <thereshouldbenoheader.h>]])],
+                         [pcre2_cv_xlc_nonexistent_fatal=no],
+                         [pcre2_cv_xlc_nonexistent_fatal=yes])
+      ])
+
+    if test "$pcre2_cv_xlc_nonexistent_fatal" = "no" && test "$pcre2_cv_xlc_qhaltonmsg_support" = "yes"; then
+      AC_CACHE_CHECK([whether -qhaltonmsg=CCN3296 fixes the non-existent-header issue], [pcre2_cv_xlc_qhaltonmsg_fixes],
+        [save_CFLAGS="$CFLAGS"
+        CFLAGS="$CFLAGS -qhaltonmsg=CCN3296"
+        AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <thereshouldbenoheader.h>]])],
+                          [pcre2_cv_xlc_qhaltonmsg_fixes=no],
+                          [pcre2_cv_xlc_qhaltonmsg_fixes=yes])
+        CFLAGS="$save_CFLAGS"
+        ])
+
+      if test "$pcre2_cv_xlc_qhaltonmsg_fixes" = "no"; then
+        AC_MSG_ERROR([-qhaltonmsg=CCN3296 not effective on non-existent headers])
+      fi
+
+      CFLAGS="$CFLAGS -qhaltonmsg=CCN3296"
+    fi
+
+  fi
+])

src/pcre2test.c

@@ -9628,30 +9628,34 @@ while (argc > 1 && argv[op][0] == '-' && argv[op][1] != 0)
     fprintf(stderr, "pcre2test: -S is not supported on this OS\n");
     exit(1);
 #else
-    int rc;
+    int rc = 0;
     uint32_t stack_size;
-    struct rlimit rlim;
-    if (U32OVERFLOW(uli))
+    struct rlimit rlim, rlim_old;
+    if (uli > INT32_MAX / (1024 * 1024))
       {
       fprintf(stderr, "** Argument for -S is too big\n");
       exit(1);
       }
     stack_size = (uint32_t)uli;
-    getrlimit(RLIMIT_STACK, &rlim);
+    getrlimit(RLIMIT_STACK, &rlim_old);
+    rlim = rlim_old;
     rlim.rlim_cur = stack_size * 1024 * 1024;
-    if (rlim.rlim_cur > rlim.rlim_max)
+    if (rlim.rlim_max != RLIM_INFINITY && rlim.rlim_cur > rlim.rlim_max)
       {
       fprintf(stderr,
         "pcre2test: requested stack size %luMiB is greater than hard limit ",
           (unsigned long int)stack_size);
-      if (rlim.rlim_max % (1024*1024) == 0) fprintf(stderr, "%luMiB\n",
-        (unsigned long int)(rlim.rlim_max/(1024 * 1024)));
-      else if (rlim.rlim_max % 1024 == 0) fprintf(stderr, "%luKiB\n",
-        (unsigned long int)(rlim.rlim_max/1024));
-      else fprintf(stderr, "%lu bytes\n", (unsigned long int)(rlim.rlim_max));
+      if (rlim.rlim_max % (1024*1024) == 0)
+        fprintf(stderr, "%luMiB\n", (unsigned long)(rlim.rlim_max/(1024*1024)));
+      else if (rlim.rlim_max % 1024 == 0)
+        fprintf(stderr, "%luKiB\n", (unsigned long)(rlim.rlim_max/1024));
+      else
+        fprintf(stderr, "%lu bytes\n", (unsigned long)(rlim.rlim_max));
       exit(1);
       }
-    rc = setrlimit(RLIMIT_STACK, &rlim);
+    if (rlim_old.rlim_cur != RLIM_INFINITY && rlim_old.rlim_cur <= INT32_MAX &&
+        rlim.rlim_cur > rlim_old.rlim_cur)
+      rc = setrlimit(RLIMIT_STACK, &rlim);
     if (rc != 0)
       {
       fprintf(stderr, "pcre2test: setting stack size %luMiB failed: %s\n",