testsuite/gna: add a test for #1757

2 files changed, 67 insertions, 0 deletions

diff --git a/testsuite/gna/issue1757/testm.vhdl b/testsuite/gna/issue1757/testm.vhdl
new file mode 100644
index 000000000..0b23642fd
--- /dev/null
+++ b/testsuite/gna/issue1757/testm.vhdl
@@ -0,0 +1,52 @@
+library ieee;
+use ieee.std_logic_1164.all;
+
+entity testm is
+
+port (clk : in std_logic;
+  data : in std_logic_vector(2+1 downto 0);
+  q1 : out std_logic_vector(3 downto 0)
+  );
+end testm;
+
+architecture rtl of testm is
+
+-- img_log2 function
+  function tlog2(d : positive) return natural is
+    variable tmp : positive;
+  begin
+    tmp := 1;
+    for count in 0 to d loop
+      if (tmp >= d) then
+        return count;
+      end if;
+      tmp := tmp*2;
+    end loop;
+    return d;
+  end;
+
+  constant SBITS : integer := tlog2(16);
+
+  signal fred : std_logic_vector(SBITS - 1 downto 0);
+
+begin
+
+  fred <= data;
+
+  process (fred)
+  begin
+    case (fred(1 downto 0)) is
+      when "00" =>
+        q1 <= data;
+
+      when "01" =>
+        q1 <= "0000";
+
+      when "10" =>
+        q1 <= data;
+
+      when others  =>
+        q1 <= "1111";
+    end case;
+  end process;
+end rtl;
diff --git a/testsuite/gna/issue1757/testsuite.sh b/testsuite/gna/issue1757/testsuite.sh
new file mode 100755
index 000000000..368449f1a
--- /dev/null
+++ b/testsuite/gna/issue1757/testsuite.sh
@@ -0,0 +1,15 @@
+#! /bin/sh
+
+. ../../testenv.sh
+
+analyze_failure testm.vhdl
+
+clean
+
+export GHDL_STD_FLAGS=--std=08
+analyze testm.vhdl
+elab_simulate testm
+
+clean
+
+echo "Test successful"