Rdar 28786959 3.0 branch if swift 3 digit version

include/swift/Parse/Parser.h

@@ -128,6 +128,7 @@ class Parser {
   bool ArgumentIsParameter = false;
 
   bool InPoundLineEnvironment = false;
+  bool InPoundIfEnvironment = false;
 
   LocalContext *CurLocalContext = nullptr;
 

lib/Basic/Version.cpp

@@ -293,15 +293,18 @@ bool operator>=(const class Version &lhs,
   if (lhs.empty())
     return true;
 
-  auto n = std::min(lhs.size(), rhs.size());
+  auto n = std::max(lhs.size(), rhs.size());
 
   for (size_t i = 0; i < n; ++i) {
-    if (lhs[i] < rhs[i])
+    auto lv = i < lhs.size() ? lhs[i] : 0;
+    auto rv = i < rhs.size() ? rhs[i] : 0;
+    if (lv < rv)
       return false;
-    else if (lhs[i] > rhs[i])
+    else if (lv > rv)
       return true;
   }
-  return lhs.size() >= rhs.size();
+  // Equality
+  return true;
 }
 
 std::pair<unsigned, unsigned> getSwiftNumericVersion() {

lib/Parse/ParseExpr.cpp

@@ -1430,8 +1430,9 @@ ParserResult<Expr> Parser::parseExprPostfix(Diag<> ID, bool isExprBasic) {
         SourceLoc nameLoc = consumeToken(tok::integer_literal);
 
         // Don't allow '.<integer literal>' following a numeric literal
-        // expression.
-        if (Result.isNonNull() && isa<NumberLiteralExpr>(Result.get())) {
+        // expression (unless in #if env, for 1.2.3.4 version numbers)
+        if (!InPoundIfEnvironment &&
+            Result.isNonNull() && isa<NumberLiteralExpr>(Result.get())) {
           diagnose(nameLoc, diag::numeric_literal_numeric_member)
             .highlight(Result.get()->getSourceRange());
           continue;

lib/Parse/ParseStmt.cpp

@@ -1759,7 +1759,7 @@ Parser::evaluateConditionalCompilationExpr(Expr *condition) {
 ParserResult<Stmt> Parser::parseStmtIfConfig(BraceItemListKind Kind) {
   StructureMarkerRAII ParsingDecl(*this, Tok.getLoc(),
                                   StructureMarkerKind::IfConfig);
-
+  llvm::SaveAndRestore<bool> S(InPoundIfEnvironment, true);
   ConditionalCompilationExprState ConfigState;
   bool foundActive = false;
   SmallVector<IfConfigStmtClause, 4> Clauses;

test/Parse/ConditionalCompilation/language_version.swift

@@ -43,8 +43,16 @@
 #if swift("") // expected-error {{unexpected platform condition argument: expected a unary comparison, such as '>=2.2'}}
 #endif
 
-// We won't expect three version components to work for now.
-#if swift(>=2.2.1) // expected-error {{expected named member of numeric literal}}
+#if swift(>=2.2.1)
+#endif
+
+// Check that an extra .0 doesn't make a version "bigger"; NB this test only
+// tests the fix on 3.0.1, but that's the swift version the fix was backported
+// to. On master, the fix is tested by language_version_explicit.swift
+#if swift(>=3.0.1.0)
+#else
+  // This shouldn't emit any diagnostics.
+  asdf asdf asdf asdf
 #endif
 
 #if swift(>=2.0, *) // expected-error {{expected only one argument to platform condition}}