SwiftCompilerSources: forward assertion and precondition failures to the assertion-handling in the C++ code base.

Author: eeckstein

SwiftCompilerSources/Sources/Basic/Utils.swift

@@ -21,20 +21,36 @@
 ///   case for `precondition`.
 @_transparent
 public func assert(_ condition: Bool, _ message: @autoclosure () -> String,
-                   file: StaticString = #fileID, line: UInt = #line) {
-  if !condition {
-    fatalError(message(), file: file, line: line)
-  }
+                   file: StaticString = #fileID, line: UInt = #line, function: StaticString = #function) {
+  precondition(condition, message(), file: file, line: line, function: function)
 }
 
 /// The assert function (without a message) to be used in the compiler.
 ///
 /// Unforuntately it's not possible to just add a default argument to `message` in the
 /// other `assert` function. We need to defined this overload.
+/// TODO: For some reason the compiler is not happy when adding a `function` argument.
 @_transparent
 public func assert(_ condition: Bool, file: StaticString = #fileID, line: UInt = #line) {
-  if !condition {
-    fatalError("", file: file, line: line)
+  precondition(condition, "", file: file, line: line, function: "")
+}
+
+/// The assert function to be used in the compiler.
+///
+/// This overrides the standard Swift precondition and forwards an assertion failure
+/// to the assertion-handling in the C++ code base.
+@_transparent
+public func precondition(_ condition: Bool, _ message: @autoclosure () -> String,
+                         file: StaticString = #fileID, line: UInt = #line, function: StaticString = #function) {
+  if !_fastPath(condition) {
+    let msg = message()
+    msg.withCString { msgStr in
+      file.withUTF8Buffer { fileBytes in
+        function.withUTF8Buffer { functionBytes in
+          assertFail(msgStr, fileBytes.baseAddress!, line, functionBytes.baseAddress!)
+        }
+      }
+    }
   }
 }
 

include/swift/Basic/BasicBridging.h

@@ -107,6 +107,9 @@ typedef uintptr_t SwiftUInt;
 #define BRIDGING_WRAPPER_NULLABLE(Node, Name) \
   BRIDGING_WRAPPER_IMPL(Node, Nullable##Name, _Nullable)
 
+void assertFail(const char * _Nonnull msg, const char * _Nonnull file,
+                SwiftUInt line, const char * _Nonnull function);
+
 //===----------------------------------------------------------------------===//
 // MARK: ArrayRef
 //===----------------------------------------------------------------------===//

lib/Basic/BasicBridging.cpp

@@ -10,6 +10,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "swift/Basic/Assertions.h"
 #include "swift/Basic/BasicBridging.h"
 #include "llvm/Support/JSON.h"
 #include "llvm/Support/raw_ostream.h"
@@ -22,6 +23,11 @@
 
 using namespace swift;
 
+void assertFail(const char * _Nonnull msg, const char * _Nonnull file,
+                SwiftUInt line, const char * _Nonnull function) {
+  ASSERT_failure(msg, file, line, function);
+}
+
 //===----------------------------------------------------------------------===//
 // MARK: BridgedStringRef
 //===----------------------------------------------------------------------===//