diff --git a/console/yap.c b/console/yap.c
index d2a66ac88..0b50ae22b 100644
--- a/console/yap.c
+++ b/console/yap.c
@@ -130,12 +130,15 @@ print_usage(void)
   fprintf(stderr,"  -l   load Prolog file\n");
   fprintf(stderr,"  -L   run Prolog file and exit\n");
   fprintf(stderr,"  -p   extra path for file-search-path\n");
-  fprintf(stderr,"  -h   Heap area in Kbytes (default: %d, minimum: %d)\n",
+  fprintf(stderr,"  -hSize   Heap area in Kbytes (default: %d, minimum: %d)\n",
 	  DefHeapSpace, MinHeapSpace);
-  fprintf(stderr,"  -s   Stack area in Kbytes (default: %d, minimum: %d)\n",
+  fprintf(stderr,"  -sSize   Stack area in Kbytes (default: %d, minimum: %d)\n",
 	  DefStackSpace, MinStackSpace);
-  fprintf(stderr,"  -t   Trail area in Kbytes (default: %d, minimum: %d)\n",
+  fprintf(stderr,"  -tSize   Trail area in Kbytes (default: %d, minimum: %d)\n",
 	  DefTrailSpace, MinTrailSpace);
+  fprintf(stderr,"  -GSize  Max Area for Global Stack\n");
+  fprintf(stderr,"  -LSize   Max Area for Local Stack (number must follow L)\n");
+  fprintf(stderr,"  -TSize   Max Area for Trail (number must follow L)\n");
   fprintf(stderr,"\n[Execution Modes]\n");
   fprintf(stderr,"  -J0  Interpreted mode (default)\n");
   fprintf(stderr,"  -J1  Mixed mode only for user predicates\n");
diff --git a/docs/yap.tex b/docs/yap.tex
index d174ebca2..f20f5653b 100644
--- a/docs/yap.tex
+++ b/docs/yap.tex
@@ -867,12 +867,22 @@ All the arguments and flags are optional and have the following meaning:
 @table @code
 @item -?
 print a short error message.
-@item -s @var{n}
-allocate @var{n} K bytes for local and global stacks
-@item -h @var{n}
-allocate @var{n} K bytes for heap and auxiliary stacks
-@item -t @var{n}
-allocate @var{n} K bytes for the trail stack
+@item -s@var{Size}
+allocate @var{Size} K bytes for local and global stacks. The user may
+ specify @t{M} bytes.
+@item -h@var{Size}
+allocate @var{Size} K bytes for heap and auxiliary stacks
+@item -t@var{Size}
+allocate @var{Size} K bytes for the trail stack
+@item -L@var{Size} 
+SWI-compatible option to allocate @var{Size} K bytes for local and global stacks, the local stack
+ cannot be expanded. To avoid confusion with the load option, @var{Size}
+ must immediately follow the letter @code{L}.
+@item -G@var{Size}
+SWI-compatible option to allocate @var{Size} K bytes for local and global stacks; the global
+stack cannot be expanded
+@item -T@var{Size}
+SWI-compatible option to allocate @var{Size} K bytes for the trail stack; the trail cannot be expanded.
 @item -l @var{YAP_FILE}
 compile the Prolog file @var{YAP_FILE} before entering the top-level.
 @item -L @var{YAP_FILE}