From: Zoltan Varga <vargaz@gmail.com>
Date: Mon, 23 Feb 2009 21:26:49 +0000 (+0000)
Subject: Avoid unnecessary GC_find_limit invocation if GC_no_dls
X-Git-Tag: gc7_3alpha2~235
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=db0da19174f2c9ee4fc90c133190a0e23e464ccf;p=gc

Avoid unnecessary GC_find_limit invocation if GC_no_dls
(Apply commit f5d47a1 from 'mono_libgc' branch)

* os_dep.c (GC_init_linux_data_start): Avoid the call to
GC_find_limit() if GC_no_dls is TRUE, as it is not needed and
it complicates debugging since it causes a SIGSEGV.
* os_dep.c (GC_register_data_segments): Add assertion for DATASTART.
---

diff --git a/os_dep.c b/os_dep.c
index a3f78001..e6651f45 100644
--- a/os_dep.c
+++ b/os_dep.c
@@ -461,6 +461,11 @@ GC_INNER char * GC_get_maps(void)
 
   GC_INNER void GC_init_linux_data_start(void)
   {
+        if (GC_no_dls) {
+                /* Not needed, avoids the SIGSEGV caused by     */
+                /* GC_find_limit which complicates debugging.   */
+                return;
+        }
 
 #   if defined(LINUX) || defined(HURD)
       /* Try the easy approaches first: */
@@ -1945,8 +1950,10 @@ void GC_register_data_segments(void)
         /* hanging from it.  We're on thin ice here ...                 */
         extern caddr_t sbrk(int);
 
+        GC_ASSERT(DATASTART);
         GC_add_roots_inner(DATASTART, (ptr_t)sbrk(0), FALSE);
 #     else
+        GC_ASSERT(DATASTART);
         GC_add_roots_inner(DATASTART, (ptr_t)(DATAEND), FALSE);
 #       if defined(DATASTART2)
           GC_add_roots_inner(DATASTART2, (ptr_t)(DATAEND2), FALSE);