make debugging easier in memory allocator code in perl.c and util.c

-show intermediate values to make C debugging easier
-Perl_safesysfree overwrote var where with a different value, this caused
 alot of confusion for me of trying to hunt for a pointer from a stack
 trace with conditional breakpoints, so don't change var where in an
 unoptimized build
-in Perl_safesysrealloc and Perl_safesysmalloc provide 1 exit path, so
 the returned value is easily seen and BPed on unoptimized builds

1 files changed, 5 insertions, 2 deletions

diff --git a/perl.c b/perl.c
index a5f159224e..eb875fcf47 100644
--- a/perl.c
+++ b/perl.c
@@ -1364,8 +1364,11 @@ perl_free(pTHXx)
 			    "free this thread's memory\n");
 		PL_debug &= ~ DEBUG_m_FLAG;
 	    }
-	    while(aTHXx->Imemory_debug_header.next != &(aTHXx->Imemory_debug_header))
-		safesysfree(PERL_MEMORY_DEBUG_HEADER_SIZE + (char *)(aTHXx->Imemory_debug_header.next));
+	    while(aTHXx->Imemory_debug_header.next != &(aTHXx->Imemory_debug_header)){
+		char * next = (char *)(aTHXx->Imemory_debug_header.next);
+		Malloc_t ptr = PERL_MEMORY_DEBUG_HEADER_SIZE + next;
+		safesysfree(ptr);
+	    }
 	    PL_debug = old_debug;
 	}
     }