Fix AIX port.

* configure.ac (DATA_START, DATA_SEG_BITS): Set to 0x20000000 on AIX.
(GC_MARK_STACK): Do not set to GC_USE_GCPROS_AS_BEFORE, as that
runs afoul of some other bug in Emacs, and the default value
GC_MAKE_GCPROS_NOOPS has been tested and works.
* src/lisp.h (XPNTR) [!USE_LSB_TAG && DATA_SEG_BITS]:
Fix bug introduced in 2012-07-27 change.  DATA_SEG_BITS, if set,
was #undeffed earlier, so it cannot be used as a macro here.
Use the constant and not the macro.  Tested on AIX.
* src/unexaix.c: Revert 2013-02-11 and 2013-02-12 changes to this
file.  They're almost surely OK but we're just before a release so
we should avoid changes unless they're clearly needed.  Instead,
make the following minor change:
(ADDR_CORRECT): New macro.

Fixes: debbugs:13650

3 files changed, 64 insertions, 49 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index e1b8a23e6b2..e283d2bb48c 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,16 @@
+2013-02-14  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Fix AIX port (Bug#13650).
+        * lisp.h (XPNTR) [!USE_LSB_TAG && DATA_SEG_BITS]:
+        Fix bug introduced in 2012-07-27 change.  DATA_SEG_BITS, if set,
+        was #undeffed earlier, so it cannot be used as a macro here.
+        Use the constant and not the macro.
+        * unexaix.c: Revert 2013-02-11 and 2013-02-12 changes to this
+        file.  They're almost surely OK but we're just before a release so
+        we should avoid changes unless they're clearly needed.  Instead,
+        make the following minor change:
+        (ADDR_CORRECT): New macro.
+
 2013-02-13  Eli Zaretskii  <eliz@gnu.org>
 
         * w32proc.c (new_child): If no vacant slots are found in
diff --git a/src/lisp.h b/src/lisp.h
index a62842c117a..eca3caefd8c 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -496,13 +496,9 @@ static EMACS_INT const VALMASK
   (XIL ((EMACS_INT) ((EMACS_UINT) (type) << VALBITS)  \
         + ((intptr_t) (ptr) & VALMASK)))
 
-#if DATA_SEG_BITS
 /* DATA_SEG_BITS forces extra bits to be or'd in with any pointers
    which were stored in a Lisp_Object.  */
 #define XPNTR(a) ((uintptr_t) ((XLI (a) & VALMASK)) | DATA_SEG_BITS))
-#else
-#define XPNTR(a) ((uintptr_t) (XLI (a) & VALMASK))
-#endif
 
 #endif /* not USE_LSB_TAG */
 
diff --git a/src/unexaix.c b/src/unexaix.c
index da44480fdca..885d7a9f6d7 100644
--- a/src/unexaix.c
+++ b/src/unexaix.c
@@ -51,8 +51,6 @@ what you give them.   Help stamp out software-hoarding!  */
 #include "getpagesize.h"
 
 #include <sys/types.h>
-#include <inttypes.h>
-#include <stdarg.h>
 #include <stdio.h>
 #include <sys/stat.h>
 #include <errno.h>
@@ -61,8 +59,10 @@ what you give them.   Help stamp out software-hoarding!  */
 
 #include "mem-limits.h"
 
-extern char _data[];
-extern char _text[];
+char *start_of_text (void);                     /* Start of text */
+
+extern int _data;
+extern int _text;
 
 #include <filehdr.h>
 #include <aouthdr.h>
@@ -71,15 +71,15 @@ extern char _text[];
 
 static struct filehdr f_hdr;            /* File header */
 static struct aouthdr f_ohdr;           /* Optional file header (a.out) */
-static off_t bias;                      /* Bias to add for growth */
-static off_t lnnoptr;                   /* Pointer to line-number info within file */
+static long bias;                       /* Bias to add for growth */
+static long lnnoptr;                    /* Pointer to line-number info within file */
 
-static off_t text_scnptr;
-static off_t data_scnptr;
+static long text_scnptr;
+static long data_scnptr;
 #define ALIGN(val, pwr) (((val) + ((1L<<(pwr))-1)) & ~((1L<<(pwr))-1))
-static off_t load_scnptr;
-static off_t orig_load_scnptr;
-static off_t orig_data_scnptr;
+static long load_scnptr;
+static long orig_load_scnptr;
+static long orig_data_scnptr;
 static int unrelocate_symbols (int, int, const char *, const char *);
 
 #ifndef MAX_SECTIONS
@@ -92,30 +92,26 @@ static int pagemask;
 
 #include "lisp.h"
 
-static _Noreturn void
+static void
 report_error (const char *file, int fd)
 {
   if (fd)
-    {
-      int failed_errno = errno;
-      close (fd);
-      errno = failed_errno;
-    }
+    close (fd);
   report_file_error ("Cannot unexec", Fcons (build_string (file), Qnil));
 }
 
-#define ERROR0(msg) report_error_1 (new, msg)
-#define ERROR1(msg,x) report_error_1 (new, msg, x)
-#define ERROR2(msg,x,y) report_error_1 (new, msg, x, y)
+#define ERROR0(msg) report_error_1 (new, msg, 0, 0); return -1
+#define ERROR1(msg,x) report_error_1 (new, msg, x, 0); return -1
+#define ERROR2(msg,x,y) report_error_1 (new, msg, x, y); return -1
 
-static _Noreturn void ATTRIBUTE_FORMAT_PRINTF (2, 3)
-report_error_1 (int fd, const char *msg, ...)
+#undef ADDR_CORRECT
+#define ADDR_CORRECT(x) ((int)(x))
+
+static void
+report_error_1 (int fd, const char *msg, int a1, int a2)
 {
-  va_list ap;
   close (fd);
-  va_start (ap, msg);
-  verror (msg, ap);
-  va_end (ap);
+  error (msg, a1, a2);
 }
 
 static int make_hdr (int, int, const char *, const char *);
@@ -170,8 +166,8 @@ make_hdr (int new, int a_out,
           const char *a_name, const char *new_name)
 {
   int scns;
-  uintptr_t bss_start;
-  uintptr_t data_start;
+  unsigned int bss_start;
+  unsigned int data_start;
 
   struct scnhdr section[MAX_SECTIONS];
   struct scnhdr * f_thdr;               /* Text section header */
@@ -186,17 +182,17 @@ make_hdr (int new, int a_out,
   pagemask = getpagesize () - 1;
 
   /* Adjust text/data boundary. */
-  data_start = (uintptr_t) _data;
+  data_start = (long) start_of_data ();
+  data_start = ADDR_CORRECT (data_start);
 
   data_start = data_start & ~pagemask; /* (Down) to page boundary. */
 
-  bss_start = (uintptr_t) sbrk (0) + pagemask;
+  bss_start = ADDR_CORRECT (sbrk (0)) + pagemask;
   bss_start &= ~ pagemask;
 
   if (data_start > bss_start)   /* Can't have negative data size. */
     {
-      ERROR2 (("unexec: data_start (0x%"PRIxPTR
-               ") can't be greater than bss_start (0x%"PRIxPTR")"),
+      ERROR2 ("unexec: data_start (%u) can't be greater than bss_start (%u)",
               data_start, bss_start);
     }
 
@@ -286,7 +282,7 @@ make_hdr (int new, int a_out,
 
   /* fix scnptr's */
   {
-    off_t ptr = section[0].s_scnptr;
+    ulong ptr = section[0].s_scnptr;
 
     bias = -1;
     for (scns = 0; scns < f_hdr.f_nscns; scns++)
@@ -382,12 +378,12 @@ copy_text_and_data (int new)
   char *end;
   char *ptr;
 
-  lseek (new, text_scnptr, SEEK_SET);
-  ptr = _text + text_scnptr;
+  lseek (new, (long) text_scnptr, SEEK_SET);
+  ptr = start_of_text () + text_scnptr;
   end = ptr + f_ohdr.tsize;
   write_segment (new, ptr, end);
 
-  lseek (new, data_scnptr, SEEK_SET);
+  lseek (new, (long) data_scnptr, SEEK_SET);
   ptr = (char *) f_ohdr.data_start;
   end = ptr + f_ohdr.dsize;
   write_segment (new, ptr, end);
@@ -400,6 +396,7 @@ static void
 write_segment (int new, char *ptr, char *end)
 {
   int i, nwrite, ret;
+  char buf[80];
   char zeros[UnexBlockSz];
 
   for (i = 0; ptr < end;)
@@ -420,13 +417,9 @@ write_segment (int new, char *ptr, char *end)
         }
       else if (nwrite != ret)
         {
-          int write_errno = errno;
-          char buf[1000];
-          void *addr = ptr;
           sprintf (buf,
-                   "unexec write failure: addr %p, fileno %d, size 0x%x, wrote 0x%x, errno %d",
-                   addr, new, nwrite, ret, errno);
-          errno = write_errno;
+                   "unexec write failure: addr 0x%lx, fileno %d, size 0x%x, wrote 0x%x, errno %d",
+                   (unsigned long)ptr, new, nwrite, ret, errno);
           PERROR (buf);
         }
       i += nwrite;
@@ -547,13 +540,13 @@ unrelocate_symbols (int new, int a_out,
   int i;
   LDHDR ldhdr;
   LDREL ldrel;
-  off_t t_reloc = (intptr_t) _text - f_ohdr.text_start;
+  ulong t_reloc = (ulong) &_text - f_ohdr.text_start;
 #ifndef ALIGN_DATA_RELOC
-  off_t d_reloc = (intptr_t) _data - f_ohdr.data_start;
+  ulong d_reloc = (ulong) &_data - f_ohdr.data_start;
 #else
   /* This worked (and was needed) before AIX 4.2.
      I have no idea why. -- Mike */
-  off_t d_reloc = (intptr_t) _data - ALIGN (f_ohdr.data_start, 2);
+  ulong d_reloc = (ulong) &_data - ALIGN (f_ohdr.data_start, 2);
 #endif
   int * p;
 
@@ -638,3 +631,16 @@ unrelocate_symbols (int new, int a_out,
     }
   return 0;
 }
+
+/*
+ *      Return the address of the start of the text segment prior to
+ *      doing an unexec.  After unexec the return value is undefined.
+ *      See crt0.c for further explanation and _start.
+ *
+ */
+
+char *
+start_of_text (void)
+{
+  return ((char *) 0x10000000);
+}