Add --max-stack-alloc option, check stack allocation of complex object.

Fix #692

3 files changed, 37 insertions, 0 deletions

diff --git a/src/grt/grt-lib.adb b/src/grt/grt-lib.adb
index 7597bcfc4..0bb9c2e36 100644
--- a/src/grt/grt-lib.adb
+++ b/src/grt/grt-lib.adb
@@ -275,6 +275,19 @@ package body Grt.Lib is
       return Ghdl_I64_Exp_1 (V, E);
    end Ghdl_I64_Exp;
 
+   procedure Ghdl_Check_Stack_Allocation (Size : Ghdl_Index_Type)
+   is
+      Bt : Backtrace_Addrs;
+   begin
+      if Size >= Max_Stack_Allocation then
+         Save_Backtrace (Bt, 1);
+         Error_S ("declaration of a too large object (");
+         Diag_C (Natural (Size / 1024));
+         Diag_C (" KB)");
+         Error_E_Call_Stack (Bt);
+      end if;
+   end Ghdl_Check_Stack_Allocation;
+
    function C_Malloc (Size : Ghdl_Index_Type) return Ghdl_Ptr;
    pragma Import (C, C_Malloc, "malloc");
 
diff --git a/src/grt/grt-lib.ads b/src/grt/grt-lib.ads
index 646cdd5fb..167ea98e5 100644
--- a/src/grt/grt-lib.ads
+++ b/src/grt/grt-lib.ads
@@ -70,6 +70,11 @@ package Grt.Lib is
    function Ghdl_I32_Exp (V : Ghdl_I32; E : Std_Integer) return Ghdl_I32;
    function Ghdl_I64_Exp (V : Ghdl_I64; E : Std_Integer) return Ghdl_I64;
 
+   --  Called before allocation of large (complex) objects.
+   procedure Ghdl_Check_Stack_Allocation (Size : Ghdl_Index_Type);
+
+   Max_Stack_Allocation : Ghdl_Index_Type := 128 * 1024;
+
    function Ghdl_Malloc (Size : Ghdl_Index_Type) return Ghdl_Ptr;
 
    --  Allocate and clear SIZE bytes.
@@ -122,6 +127,9 @@ private
                   "__ghdl_direction_check_failed");
    pragma Export (C, Ghdl_Program_Error, "__ghdl_program_error");
 
+   pragma Export (C, Ghdl_Check_Stack_Allocation,
+                  "__ghdl_check_stack_allocation");
+
    pragma Export (C, Ghdl_Malloc, "__ghdl_malloc");
    pragma Export (C, Ghdl_Malloc0, "__ghdl_malloc0");
    pragma Export (C, Ghdl_Deallocate, "__ghdl_deallocate");
diff --git a/src/grt/grt-options.adb b/src/grt/grt-options.adb
index 5b154e4a5..d93ad9e58 100644
--- a/src/grt/grt-options.adb
+++ b/src/grt/grt-options.adb
@@ -56,6 +56,7 @@ package body Grt.Options is
       P ("       X is expressed as a time value, without spaces: 1ns, ps...");
       P (" --stop-delta=X    stop the simulation cycle after X delta");
       P (" --expect-failure  invert exit status");
+      P (" --max-stack-alloc=X  error if variables are larger than X KB");
       P (" --no-run          do not simulate, only elaborate");
       P (" --unbuffered      disable buffering on stdout, stderr and");
       P ("                   files opened in write or append mode (TEXTIO).");
@@ -272,6 +273,21 @@ package body Grt.Options is
          Warning ("option --stack-size is deprecated");
       elsif Len >= 17 and then Option (1 .. 17) = "--stack-max-size=" then
          Warning ("option --stack-max-size is deprecated");
+      elsif Len >= 18 and then Option (1 .. 18) = "--max-stack-alloc=" then
+         declare
+            Ok : Boolean;
+            Pos : Natural;
+            Val : Integer_64;
+         begin
+            Extract_Integer (Option (19 .. Len), Ok, Val, Pos);
+            if not Ok or else Pos <= Len then
+               Error_S ("bad value in '");
+               Diag_C (Option);
+               Error_E ("'");
+            else
+               Lib.Max_Stack_Allocation := Ghdl_Index_Type (Val * 1024);
+            end if;
+         end;
       elsif Len >= 11 and then Option (1 .. 11) = "--activity=" then
          if Option (12 .. Len) = "none" then
             Flag_Activity := Activity_None;