diff --git a/clang/lib/Basic/Diagnostic.cpp b/clang/lib/Basic/Diagnostic.cpp
--- a/clang/lib/Basic/Diagnostic.cpp
+++ b/clang/lib/Basic/Diagnostic.cpp
@@ -812,7 +812,7 @@
       getArgKind(0) == DiagnosticsEngine::ak_std_string) {
     const std::string &S = getArgStdStr(0);
     for (char c : S) {
-      if (llvm::sys::locale::isPrint(c) || c == '\t') {
+      if (llvm::sys::locale::isPrint(c) || c == '\t' || c == '\n') {
         OutStr.push_back(c);
       }
     }
diff --git a/clang/lib/Frontend/TextDiagnosticPrinter.cpp b/clang/lib/Frontend/TextDiagnosticPrinter.cpp
--- a/clang/lib/Frontend/TextDiagnosticPrinter.cpp
+++ b/clang/lib/Frontend/TextDiagnosticPrinter.cpp
@@ -116,9 +116,24 @@
   SmallString<100> OutStr;
   Info.FormatDiagnostic(OutStr);
 
-  llvm::raw_svector_ostream DiagMessageStream(OutStr);
+  // If the diagnostic message is formatted into multiple lines, split the
+  // first line and feed it into printDiagnosticOptions so that we print the
+  // options only on the first line instead of the last line.
+  SmallString<100> InitStr;
+  size_t NewlinePos = OutStr.find_first_of('\n');
+  if (NewlinePos != StringRef::npos) {
+    for (size_t I = 0; I != NewlinePos; ++I)
+      InitStr.push_back(OutStr[I]);
+  } else
+    InitStr = OutStr;
+
+  llvm::raw_svector_ostream DiagMessageStream(InitStr);
   printDiagnosticOptions(DiagMessageStream, Level, Info, *DiagOpts);
 
+  // Append the remaining diagnostic message if there were multiple lines.
+  if (NewlinePos != StringRef::npos)
+    DiagMessageStream << OutStr.slice(NewlinePos, OutStr.size());
+
   // Keeps track of the starting position of the location
   // information (e.g., "foo.c:10:4:") that precedes the error
   // message. We use this information to determine how long the
diff --git a/clang/lib/StaticAnalyzer/Core/TextDiagnostics.cpp b/clang/lib/StaticAnalyzer/Core/TextDiagnostics.cpp
--- a/clang/lib/StaticAnalyzer/Core/TextDiagnostics.cpp
+++ b/clang/lib/StaticAnalyzer/Core/TextDiagnostics.cpp
@@ -90,13 +90,19 @@
          E = Diags.end();
          I != E; ++I) {
       const PathDiagnostic *PD = *I;
+      std::string OutStr;
       std::string WarningMsg = (DiagOpts.ShouldDisplayDiagnosticName
                                     ? " [" + PD->getCheckerName() + "]"
                                     : "")
                                    .str();
 
-      reportPiece(WarnID, PD->getLocation().asLocation(),
-                  (PD->getShortDescription() + WarningMsg).str(),
+      size_t NewlinePos = PD->getShortDescription().find_first_of('\n');
+      if (NewlinePos != std::string::npos)
+        OutStr = PD->getShortDescription().str().insert(NewlinePos, WarningMsg);
+      else
+        OutStr = (PD->getShortDescription() + WarningMsg).str();
+
+      reportPiece(WarnID, PD->getLocation().asLocation(), OutStr,
                   PD->path.back()->getRanges(), PD->path.back()->getFixits());
 
       // First, add extra notes, even if paths should not be included.
diff --git a/clang/test/Analysis/padding_message.cpp b/clang/test/Analysis/padding_message.cpp
--- a/clang/test/Analysis/padding_message.cpp
+++ b/clang/test/Analysis/padding_message.cpp
@@ -1,11 +1,11 @@
 // RUN: %clang_analyze_cc1 -triple x86_64-unknown-linux -std=c++14 -analyzer-checker=optin.performance -analyzer-config optin.performance.Padding:AllowedPad=2 -verify %s
 
 // expected-warning@+7{{\
-Excessive padding in 'struct IntSandwich' (6 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-i, \
-c1, \
-c2, \
+Excessive padding in 'struct IntSandwich' (6 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+i, \n\
+c1, \n\
+c2, \n\
 }}
 struct IntSandwich {
   char c1;
@@ -14,11 +14,11 @@
 };
 
 // expected-warning@+7{{\
-Excessive padding in 'struct TurDuckHen' (6 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-i, \
-c1, \
-c2, \
+Excessive padding in 'struct TurDuckHen' (6 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+i, \n\
+c1, \n\
+c2, \n\
 }}
 struct TurDuckHen {
   char c1;
@@ -29,15 +29,15 @@
 #pragma pack(push)
 #pragma pack(2)
 // expected-warning@+11{{\
-Excessive padding in 'struct SmallIntSandwich' (4 padding bytes, where 0 is optimal). \
-Optimal fields order: \
-i1, \
-i2, \
-i3, \
-c1, \
-c2, \
-c3, \
-c4, \
+Excessive padding in 'struct SmallIntSandwich' (4 padding bytes, where 0 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+i1, \n\
+i2, \n\
+i3, \n\
+c1, \n\
+c2, \n\
+c3, \n\
+c4, \n\
 }}
 struct SmallIntSandwich {
   char c1;
@@ -57,11 +57,11 @@
 };
 
 // expected-warning@+7{{\
-Excessive padding in 'struct HoldsAUnion' (6 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-u, \
-c1, \
-c2, \
+Excessive padding in 'struct HoldsAUnion' (6 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+u, \n\
+c1, \n\
+c2, \n\
 }}
 struct HoldsAUnion {
   char c1;
@@ -78,11 +78,11 @@
 };
 
 // expected-warning@+7{{\
-Excessive padding in 'struct StructSandwich' (6 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-m, \
-s, \
-s2, \
+Excessive padding in 'struct StructSandwich' (6 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+m, \n\
+s, \n\
+s2, \n\
 }}
 struct StructSandwich {
   struct SmallCharArray s;
@@ -91,11 +91,11 @@
 };
 
 // expected-warning@+7{{\
-Excessive padding in 'TypedefSandwich' (6 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-i, \
-c1, \
-c2, \
+Excessive padding in 'TypedefSandwich' (6 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+i, \n\
+c1, \n\
+c2, \n\
 }}
 typedef struct {
   char c1;
@@ -104,11 +104,11 @@
 } TypedefSandwich;
 
 // expected-warning@+7{{\
-Excessive padding in 'struct StructAttrAlign' (10 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-i, \
-c1, \
-c2, \
+Excessive padding in 'struct StructAttrAlign' (10 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+i, \n\
+c1, \n\
+c2, \n\
 }}
 struct StructAttrAlign {
   char c1;
@@ -117,12 +117,12 @@
 } __attribute__((aligned(8)));
 
 // expected-warning@+8{{\
-Excessive padding in 'struct OverlyAlignedChar' (8185 padding bytes, where 4089 is optimal). \
-Optimal fields order: \
-c, \
-c1, \
-c2, \
-x, \
+Excessive padding in 'struct OverlyAlignedChar' (8185 padding bytes, where 4089 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+c, \n\
+c1, \n\
+c2, \n\
+x, \n\
 }}
 struct OverlyAlignedChar {
   char c1;
@@ -132,11 +132,11 @@
 };
 
 // expected-warning@+7{{\
-Excessive padding in 'struct HoldsOverlyAlignedChar' (8190 padding bytes, where 4094 is optimal). \
-Optimal fields order: \
-o, \
-c1, \
-c2, \
+Excessive padding in 'struct HoldsOverlyAlignedChar' (8190 padding bytes, where 4094 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+o, \n\
+c1, \n\
+c2, \n\
 }}
 struct HoldsOverlyAlignedChar {
   char c1;
@@ -146,11 +146,11 @@
 
 void internalStructFunc() {
   // expected-warning@+7{{\
-Excessive padding in 'struct X' (6 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-t, \
-c1, \
-c2, \
+Excessive padding in 'struct X' (6 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+t, \n\
+c1, \n\
+c2, \n\
 }}
   struct X {
     char c1;
@@ -162,11 +162,11 @@
 
 void typedefStructFunc() {
   // expected-warning@+7{{\
-Excessive padding in 'S' (6 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-t, \
-c1, \
-c2, \
+Excessive padding in 'S' (6 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+t, \n\
+c1, \n\
+c2, \n\
 }}
   typedef struct {
     char c1;
@@ -177,11 +177,11 @@
 }
 
 // expected-warning@+7{{\
-Excessive padding in 'struct DefaultAttrAlign' (22 padding bytes, where 6 is optimal). \
-Optimal fields order: \
-i, \
-c1, \
-c2, \
+Excessive padding in 'struct DefaultAttrAlign' (22 padding bytes, where 6 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+i, \n\
+c1, \n\
+c2, \n\
 }}
 struct DefaultAttrAlign {
   char c1;
@@ -190,11 +190,11 @@
 } __attribute__((aligned));
 
 // expected-warning@+7{{\
-Excessive padding in 'struct SmallArrayShortSandwich' (2 padding bytes, where 0 is optimal). \
-Optimal fields order: \
-s, \
-c1, \
-c2, \
+Excessive padding in 'struct SmallArrayShortSandwich' (2 padding bytes, where 0 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+s, \n\
+c1, \n\
+c2, \n\
 }}
 struct SmallArrayShortSandwich {
   char c1;
@@ -203,11 +203,11 @@
 } ShortArray[20];
 
 // expected-warning@+7{{\
-Excessive padding in 'struct SmallArrayInFunc' (2 padding bytes, where 0 is optimal). \
-Optimal fields order: \
-s, \
-c1, \
-c2, \
+Excessive padding in 'struct SmallArrayInFunc' (2 padding bytes, where 0 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+s, \n\
+c1, \n\
+c2, \n\
 }}
 struct SmallArrayInFunc {
   char c1;
@@ -220,11 +220,11 @@
 }
 
 // expected-warning@+7{{\
-Excessive padding in 'class VirtualIntSandwich' (10 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-i, \
-c1, \
-c2, \
+Excessive padding in 'class VirtualIntSandwich' (10 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+i, \n\
+c1, \n\
+c2, \n\
 }}
 class VirtualIntSandwich {
   virtual void foo() {}
@@ -235,12 +235,12 @@
 
 // constructed so as not to have tail padding
 // expected-warning@+8{{\
-Excessive padding in 'class InnerPaddedB' (6 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-i1, \
-i2, \
-c1, \
-c2, \
+Excessive padding in 'class InnerPaddedB' (6 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+i1, \n\
+i2, \n\
+c1, \n\
+c2, \n\
 }}
 class InnerPaddedB {
   char c1;
@@ -252,11 +252,11 @@
 class Empty {}; // no-warning
 
 // expected-warning@+7{{\
-Excessive padding in 'class LotsOfSpace' (6 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-i, \
-e1, \
-e2, \
+Excessive padding in 'class LotsOfSpace' (6 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+i, \n\
+e1, \n\
+e2, \n\
 }}
 class LotsOfSpace {
   Empty e1;
@@ -265,20 +265,20 @@
 };
 
 // expected-warning@+7{{\
-Excessive padding in 'struct TypedefSandwich2' (6 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-t, \
-c1, \
-c2, \
+Excessive padding in 'struct TypedefSandwich2' (6 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+t, \n\
+c1, \n\
+c2, \n\
 }}
 typedef struct TypedefSandwich2 {
   char c1;
   // expected-warning@+7{{\
-Excessive padding in 'TypedefSandwich2::NestedTypedef' (6 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-i, \
-c1, \
-c2, \
+Excessive padding in 'TypedefSandwich2::NestedTypedef' (6 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+i, \n\
+c1, \n\
+c2, \n\
 }}
   typedef struct {
     char c1;
@@ -292,11 +292,11 @@
 template <typename T>
 struct Foo {
   // expected-warning@+7{{\
-Excessive padding in 'struct Foo<int>::Nested' (6 padding bytes, where 2 is optimal). \
-Optimal fields order: \
-t, \
-c1, \
-c2, \
+Excessive padding in 'struct Foo<int>::Nested' (6 padding bytes, where 2 is optimal).  [optin.performance.Padding]\n\
+Optimal fields order: \n\
+t, \n\
+c1, \n\
+c2, \n\
 }}
   struct Nested {
     char c1;