[RFA/RFC] Fix broken user-thread debugging on x86-solaris

[Joel Brobecker]

> I have no preference whatsoever; just whatever is easier in practice.

That works for me :) - we can always adjust later if I hear some more
comments. Here is what I ended up checking-in (I used the opportunity
to add a little comment explaining why the function is needed, as well as
grouping the two LDT-related functions in procfs.c together).

2008-02-12  Joel Brobecker  <brobecker@gnat.com>

        * sol-thread.c: Replace use of TM_I386SOL2_H by an expression
        that is true only on x86-solaris and x86_64-solaris.
        * procfs.c: Likewise. Move procfs_find_LDT_entry up together
        with proc_get_LDT_entry.

Tested on x86-solaris, no regression. Applied to head and branch.

Thanks!
-- 
Joel
-------------- next part --------------
Index: sol-thread.c
===================================================================
RCS file: /cvs/src/src/gdb/sol-thread.c,v
retrieving revision 1.63
diff -u -p -r1.63 sol-thread.c
--- sol-thread.c	23 Jan 2008 11:26:28 -0000	1.63
+++ sol-thread.c	12 Mar 2008 18:39:54 -0000
@@ -1283,9 +1283,12 @@ ps_pdmodel (gdb_ps_prochandle_t ph, int 
 }
 #endif /* PR_MODEL_LP64 */
 
-#ifdef TM_I386SOL2_H
+#if (defined(__i386__) || defined(__x86_64__)) && defined (sun)
 
-/* Reads the local descriptor table of a LWP.  */
+/* Reads the local descriptor table of a LWP.
+
+   This function is necessary on x86-solaris only.  Without it, the loading
+   of libthread_db would fail because of ps_lgetLDT being undefined.  */
 
 ps_err_e
 ps_lgetLDT (gdb_ps_prochandle_t ph, lwpid_t lwpid,
@@ -1311,7 +1314,7 @@ ps_lgetLDT (gdb_ps_prochandle_t ph, lwpi
     /* LDT not found.  */
     return PS_ERR;
 }
-#endif /* TM_I386SOL2_H */
+#endif
 
 
 /* Convert PTID to printable form.  */
Index: procfs.c
===================================================================
RCS file: /cvs/src/src/gdb/procfs.c,v
retrieving revision 1.85
diff -u -p -r1.85 procfs.c
--- procfs.c	25 Jan 2008 00:09:49 -0000	1.85
+++ procfs.c	12 Mar 2008 18:39:55 -0000
@@ -2919,7 +2919,7 @@ proc_set_watchpoint (procinfo *pi, CORE_
 #endif
 }
 
-#ifdef TM_I386SOL2_H		/* Is it hokey to use this? */
+#if (defined(__i386__) || defined(__x86_64__)) && defined (sun)
 
 #include <sys/sysi86.h>
 
@@ -3011,7 +3011,45 @@ proc_get_LDT_entry (procinfo *pi, int ke
 #endif
 }
 
-#endif /* TM_I386SOL2_H */
+/*
+ * Function: procfs_find_LDT_entry
+ *
+ * Input:
+ *   ptid_t ptid;	// The GDB-style pid-plus-LWP.
+ *
+ * Return:
+ *   pointer to the corresponding LDT entry.
+ */
+
+struct ssd *
+procfs_find_LDT_entry (ptid_t ptid)
+{
+  gdb_gregset_t *gregs;
+  int            key;
+  procinfo      *pi;
+
+  /* Find procinfo for the lwp. */
+  if ((pi = find_procinfo (PIDGET (ptid), TIDGET (ptid))) == NULL)
+    {
+      warning (_("procfs_find_LDT_entry: could not find procinfo for %d:%d."),
+	       PIDGET (ptid), TIDGET (ptid));
+      return NULL;
+    }
+  /* get its general registers. */
+  if ((gregs = proc_get_gregs (pi)) == NULL)
+    {
+      warning (_("procfs_find_LDT_entry: could not read gregs for %d:%d."),
+	       PIDGET (ptid), TIDGET (ptid));
+      return NULL;
+    }
+  /* Now extract the GS register's lower 16 bits. */
+  key = (*gregs)[GS] & 0xffff;
+
+  /* Find the matching entry and return it. */
+  return proc_get_LDT_entry (pi, key);
+}
+
+#endif
 
 /* =============== END, non-thread part of /proc  "MODULE" =============== */
 
@@ -5331,46 +5369,6 @@ procfs_stopped_by_watchpoint (ptid_t pti
   return 0;
 }
 
-#ifdef TM_I386SOL2_H
-/*
- * Function: procfs_find_LDT_entry
- *
- * Input:
- *   ptid_t ptid;	// The GDB-style pid-plus-LWP.
- *
- * Return:
- *   pointer to the corresponding LDT entry.
- */
-
-struct ssd *
-procfs_find_LDT_entry (ptid_t ptid)
-{
-  gdb_gregset_t *gregs;
-  int            key;
-  procinfo      *pi;
-
-  /* Find procinfo for the lwp. */
-  if ((pi = find_procinfo (PIDGET (ptid), TIDGET (ptid))) == NULL)
-    {
-      warning (_("procfs_find_LDT_entry: could not find procinfo for %d:%d."),
-	       PIDGET (ptid), TIDGET (ptid));
-      return NULL;
-    }
-  /* get its general registers. */
-  if ((gregs = proc_get_gregs (pi)) == NULL)
-    {
-      warning (_("procfs_find_LDT_entry: could not read gregs for %d:%d."),
-	       PIDGET (ptid), TIDGET (ptid));
-      return NULL;
-    }
-  /* Now extract the GS register's lower 16 bits. */
-  key = (*gregs)[GS] & 0xffff;
-
-  /* Find the matching entry and return it. */
-  return proc_get_LDT_entry (pi, key);
-}
-#endif /* TM_I386SOL2_H */
-
 /*
  * Memory Mappings Functions:
  */