Index: lib/Driver/ToolChains/Clang.cpp
===================================================================
--- lib/Driver/ToolChains/Clang.cpp
+++ lib/Driver/ToolChains/Clang.cpp
@@ -2360,9 +2360,6 @@
   // Treat blocks as analysis entry points.
   CmdArgs.push_back("-analyzer-opt-analyze-nested-blocks");
 
-  // Enable compatilibily mode to avoid analyzer-config related errors.
-  CmdArgs.push_back("-analyzer-config-compatibility-mode=true");
-
   // Add default argument set.
   if (!Args.hasArg(options::OPT__analyzer_no_default_checks)) {
     CmdArgs.push_back("-analyzer-checker=core");
@@ -3694,6 +3691,17 @@
   if (isa<AnalyzeJobAction>(JA))
     RenderAnalyzerOptions(Args, CmdArgs, Triple, Input);
 
+  {
+    auto AnalyzerConfigArg =
+        llvm::find_if(CmdArgs, [] (StringRef Arg) {
+                                 return Arg.contains("-analyzer-config");
+                               });
+
+    // Enable compatilibily mode to avoid analyzer-config related errors.
+    if (AnalyzerConfigArg != CmdArgs.end())
+      CmdArgs.push_back("-analyzer-config-compatibility-mode=true");
+  }
+
   CheckCodeGenerationOptions(D, Args);
 
   unsigned FunctionAlignment = ParseFunctionAlignment(TC, Args);
Index: test/Analysis/invalid-analyzer-config-value.c
===================================================================
--- test/Analysis/invalid-analyzer-config-value.c
+++ test/Analysis/invalid-analyzer-config-value.c
@@ -66,6 +66,12 @@
 
 // CHECK-NO-COMPAT: error: unknown analyzer-config 'no-false-positives'
 
+
+// Test the driver properly using "analyzer-config-compatibility-mode=true",
+// even if -analyze isn't specified.
+// RUN: %clang --analyze -Xclang -analyzer-config -Xclang remember=TheVasa %s
+
+
 // expected-no-diagnostics
 
 int main() {}