Analyze inline assembly variable declarations for invalid or shadowing names.

test/libsolidity/syntaxTests/inlineAssembly/invalid/variable_declaration_suffix_offset.sol

@@ -0,0 +1,15 @@
+contract C {
+    function f() public pure {
+        assembly {
+            let x_offset := 1
+            let x_slot := 1
+            let _offset := 1
+            let _slot := 1
+        }
+    }
+}
+// ----
+// DeclarationError: (79-87): In variable declarations _slot and _offset can not be used as a suffix.
+// DeclarationError: (109-115): In variable declarations _slot and _offset can not be used as a suffix.
+// DeclarationError: (137-144): In variable declarations _slot and _offset can not be used as a suffix.
+// DeclarationError: (166-171): In variable declarations _slot and _offset can not be used as a suffix.

test/libsolidity/syntaxTests/inlineAssembly/shadowing/argument.sol

@@ -0,0 +1,9 @@
+contract C {
+    function f(uint a) public pure {
+        assembly {
+            let a := 1
+        }
+    }
+}
+// ----
+// DeclarationError: (85-86): This declaration shadows a declaration outside the inline assembly block.

test/libsolidity/syntaxTests/inlineAssembly/shadowing/constant.sol

@@ -0,0 +1,10 @@
+contract C {
+    uint constant a;
+    function f() public pure {
+        assembly {
+            let a := 1
+        }
+    }
+}
+// ----
+// DeclarationError: (100-101): This declaration shadows a declaration outside the inline assembly block.

test/libsolidity/syntaxTests/inlineAssembly/shadowing/contract.sol

@@ -0,0 +1,9 @@
+contract C {
+    function f() public pure {
+        assembly {
+            let C := 1
+        }
+    }
+}
+// ----
+// DeclarationError: (79-80): This declaration shadows a declaration outside the inline assembly block.

test/libsolidity/syntaxTests/inlineAssembly/shadowing/function.sol

@@ -0,0 +1,9 @@
+contract C {
+    function f() public pure {
+        assembly {
+            let f := 1
+        }
+    }
+}
+// ----
+// DeclarationError: (79-80): This declaration shadows a declaration outside the inline assembly block.

test/libsolidity/syntaxTests/inlineAssembly/shadowing/local_variable.sol

@@ -0,0 +1,10 @@
+contract C {
+    function f() public pure {
+        uint a;
+        assembly {
+            let a := 1
+        }
+    }
+}
+// ----
+// DeclarationError: (95-96): This declaration shadows a declaration outside the inline assembly block.

test/libsolidity/syntaxTests/inlineAssembly/shadowing/name_clash_in_import.sol

@@ -0,0 +1,18 @@
+==== Source: a ====
+contract A
+{
+	uint constant a = 42;
+}
+==== Source: b ====
+import {A as b} from "a";
+contract B {
+    function f() public pure {
+        assembly {
+            let b := 3
+            let b.a := 4
+        }
+    }
+}
+// ----
+// DeclarationError: (b:105-106): This declaration shadows a declaration outside the inline assembly block.
+// DeclarationError: (b:128-131): The prefix of this declaration conflicts with a declaration outside the inline assembly block.

test/libsolidity/syntaxTests/inlineAssembly/shadowing/no_name_clash_in_import.sol

@@ -0,0 +1,15 @@
+==== Source: a ====
+contract A
+{
+	uint constant a = 42;
+}
+==== Source: b ====
+import {A as b} from "a";
+contract B {
+    function f() public pure {
+        assembly {
+            let A := 1
+            let A.b := 2
+        }
+    }
+}

test/libsolidity/syntaxTests/inlineAssembly/shadowing/qualified_names.sol

@@ -0,0 +1,14 @@
+contract D {
+    uint constant a;
+}
+contract C {
+    function f() public pure {
+        assembly {
+            let D.a := 1
+            let D.b := 1 // shadowing the prefix only is also an error
+        }
+    }
+}
+// ----
+// DeclarationError: (115-118): The prefix of this declaration conflicts with a declaration outside the inline assembly block.
+// DeclarationError: (140-143): The prefix of this declaration conflicts with a declaration outside the inline assembly block.