amaranth-lang · Dec 11, 2021 · Dec 11, 2021
diff --git a/amaranth/build/plat.py b/amaranth/build/plat.py
@@ -92,7 +92,7 @@ def build(self, elaboratable, name="top",
         #     may fail.
         # This is OK because even if `require_tool` succeeds, the toolchain might be broken anyway.
         # The check only serves to catch common errors earlier.
-        if do_build and (self._deprecated_toolchain_env_var not in os.environ or
+        if do_build and (self._deprecated_toolchain_env_var not in os.environ and
                          self._toolchain_env_var not in os.environ):
             for tool in self.required_tools:
                 require_tool(tool)

diff --git a/amaranth/hdl/ir.py b/amaranth/hdl/ir.py
@@ -34,7 +34,7 @@ def get(obj, platform):
             elif isinstance(obj, Elaboratable):
                 code = obj.elaborate.__code__
                 obj._MustUse__used = True
-                obj = obj.elaborate(platform)
+                new_obj = obj.elaborate(platform)
             elif hasattr(obj, "elaborate"):
                 warnings.warn(
                     message="Class {!r} is an elaboratable that does not explicitly inherit from "
@@ -43,15 +43,18 @@ def get(obj, platform):
                     category=RuntimeWarning,
                     stacklevel=2)
                 code = obj.elaborate.__code__
-                obj = obj.elaborate(platform)
+                new_obj = obj.elaborate(platform)
             else:
                 raise AttributeError("Object {!r} cannot be elaborated".format(obj))
-            if obj is None and code is not None:
+            if new_obj is obj:
+                raise RecursionError("Object {!r} elaborates to itself".format(obj))
+            if new_obj is None and code is not None:
                 warnings.warn_explicit(
                     message=".elaborate() returned None; missing return statement?",
                     category=UserWarning,
                     filename=code.co_filename,
                     lineno=code.co_firstlineno)
+            obj = new_obj
 
     def __init__(self):
         self.ports = SignalDict()

diff --git a/amaranth/vendor/intel.py b/amaranth/vendor/intel.py
@@ -86,6 +86,11 @@ class IntelPlatform(TemplatedPlatform):
         **TemplatedPlatform.build_script_templates,
         "build_{{name}}.sh": r"""
             # {{autogenerated}}
+            if [ -n "${{platform._deprecated_toolchain_env_var}}" ]; then
+                QUARTUS_ROOTDIR=$(dirname $(dirname "${{platform._deprecated_toolchain_env_var}}"))
+                # Quartus' qenv.sh does not work with `set -e`.
+                . "${{platform._deprecated_toolchain_env_var}}"
+            fi
             if [ -n "${{platform._toolchain_env_var}}" ]; then
                 QUARTUS_ROOTDIR=$(dirname $(dirname "${{platform._toolchain_env_var}}"))
                 # Quartus' qenv.sh does not work with `set -e`.

diff --git a/amaranth/vendor/lattice_ecp5.py b/amaranth/vendor/lattice_ecp5.py
@@ -191,6 +191,10 @@ class LatticeECP5Platform(TemplatedPlatform):
             # {{autogenerated}}
             set -e{{verbose("x")}}
             if [ -z "$BASH" ] ; then exec /bin/bash "$0" "$@"; fi
+            if [ -n "${{platform._deprecated_toolchain_env_var}}" ]; then
+                bindir=$(dirname "${{platform._deprecated_toolchain_env_var}}")
+                . "${{platform._deprecated_toolchain_env_var}}"
+            fi
             if [ -n "${{platform._toolchain_env_var}}" ]; then
                 bindir=$(dirname "${{platform._toolchain_env_var}}")
                 . "${{platform._toolchain_env_var}}"

diff --git a/amaranth/vendor/lattice_ice40.py b/amaranth/vendor/lattice_ice40.py
@@ -182,7 +182,18 @@ class LatticeICE40Platform(TemplatedPlatform):
         "build_{{name}}.sh": r"""
             # {{autogenerated}}
             set -e{{verbose("x")}}
-            if [ -n "${{platform._toolchain_env_var}}" ]; then
+            if [ -n "${{platform._deprecated_toolchain_env_var}}" ]; then
+                # LSE environment
+                export LD_LIBRARY_PATH=${{platform._deprecated_toolchain_env_var}}/LSE/bin/lin64:$LD_LIBRARY_PATH
+                export PATH=${{platform._deprecated_toolchain_env_var}}/LSE/bin/lin64:$PATH
+                export FOUNDRY=${{platform._deprecated_toolchain_env_var}}/LSE
+                # Synplify environment
+                export LD_LIBRARY_PATH=${{platform._deprecated_toolchain_env_var}}/sbt_backend/bin/linux/opt/synpwrap:$LD_LIBRARY_PATH
+                export PATH=${{platform._deprecated_toolchain_env_var}}/sbt_backend/bin/linux/opt/synpwrap:$PATH
+                export SYNPLIFY_PATH=${{platform._deprecated_toolchain_env_var}}/synpbase
+                # Common environment
+                export SBT_DIR=${{platform._deprecated_toolchain_env_var}}/sbt_backend
+            elif [ -n "${{platform._toolchain_env_var}}" ]; then
                 # LSE environment
                 export LD_LIBRARY_PATH=${{platform._toolchain_env_var}}/LSE/bin/lin64:$LD_LIBRARY_PATH
                 export PATH=${{platform._toolchain_env_var}}/LSE/bin/lin64:$PATH

diff --git a/amaranth/vendor/lattice_machxo_2_3l.py b/amaranth/vendor/lattice_machxo_2_3l.py
@@ -55,6 +55,10 @@ class LatticeMachXO2Or3LPlatform(TemplatedPlatform):
             # {{autogenerated}}
             set -e{{verbose("x")}}
             if [ -z "$BASH" ] ; then exec /bin/bash "$0" "$@"; fi
+            if [ -n "${{platform._deprecated_toolchain_env_var}}" ]; then
+                bindir=$(dirname "${{platform._deprecated_toolchain_env_var}}")
+                . "${{platform._deprecated_toolchain_env_var}}"
+            fi
             if [ -n "${{platform._toolchain_env_var}}" ]; then
                 bindir=$(dirname "${{platform._toolchain_env_var}}")
                 . "${{platform._toolchain_env_var}}"

diff --git a/amaranth/vendor/xilinx.py b/amaranth/vendor/xilinx.py
@@ -129,6 +129,7 @@ def _part(self):
             # {{autogenerated}}
             set -e{{verbose("x")}}
             if [ -z "$BASH" ] ; then exec /bin/bash "$0" "$@"; fi
+            [ -n "${{platform._deprecated_toolchain_env_var}}" ] && . "${{platform._deprecated_toolchain_env_var}}"
             [ -n "${{platform._toolchain_env_var}}" ] && . "${{platform._toolchain_env_var}}"
             {{emit_commands("sh")}}
         """,
@@ -235,6 +236,7 @@ def _part(self):
             # {{autogenerated}}
             set -e{{verbose("x")}}
             if [ -z "$BASH" ] ; then exec /bin/bash "$0" "$@"; fi
+            [ -n "${{platform._deprecated_toolchain_env_var}}" ] && . "${{platform._deprecated_toolchain_env_var}}"
             [ -n "${{platform._toolchain_env_var}}" ] && . "${{platform._toolchain_env_var}}"
             {{emit_commands("sh")}}
         """,

diff --git a/tests/test_hdl_ir.py b/tests/test_hdl_ir.py
@@ -10,13 +10,18 @@
 from .utils import *
 
 
-class BadElaboratable(Elaboratable):
+class ElaboratesToNone(Elaboratable):
     def elaborate(self, platform):
         return
 
 
+class ElaboratesToSelf(Elaboratable):
+    def elaborate(self, platform):
+        return self
+
+
 class FragmentGetTestCase(FHDLTestCase):
-    def test_get_wrong(self):
+    def test_get_wrong_none(self):
         with self.assertRaisesRegex(AttributeError,
                 r"^Object None cannot be elaborated$"):
             Fragment.get(None, platform=None)
@@ -25,7 +30,12 @@ def test_get_wrong(self):
                 r"^\.elaborate\(\) returned None; missing return statement\?$"):
             with self.assertRaisesRegex(AttributeError,
                     r"^Object None cannot be elaborated$"):
-                Fragment.get(BadElaboratable(), platform=None)
+                Fragment.get(ElaboratesToNone(), platform=None)
+
+    def test_get_wrong_self(self):
+        with self.assertRaisesRegex(RecursionError,
+                r"^Object <.+?ElaboratesToSelf.+?> elaborates to itself$"):
+            Fragment.get(ElaboratesToSelf(), platform=None)
 
 
 class FragmentGeneratedTestCase(FHDLTestCase):