diff --git a/security/manager/ssl/DataStorage.cpp b/security/manager/ssl/DataStorage.cpp
index 525e63250bd0..4d56d2a0c2c5 100644
--- a/security/manager/ssl/DataStorage.cpp
+++ b/security/manager/ssl/DataStorage.cpp
@@ -6,6 +6,7 @@
 
 #include "DataStorage.h"
 
+#include "mozilla/Assertions.h"
 #include "mozilla/ClearOnShutdown.h"
 #include "mozilla/dom/PContent.h"
 #include "mozilla/dom/ContentChild.h"
@@ -91,7 +92,7 @@ DataStorage::Init(bool& aDataWillPersist)
 {
   // Don't access the observer service or preferences off the main thread.
   if (!NS_IsMainThread()) {
-    NS_NOTREACHED("DataStorage::Init called off main thread");
+    MOZ_ASSERT_UNREACHABLE("DataStorage::Init called off main thread");
     return NS_ERROR_NOT_SAME_THREAD;
   }
 
@@ -814,7 +815,7 @@ DataStorage::NotifyObservers(const char* aTopic)
 {
   // Don't access the observer service off the main thread.
   if (!NS_IsMainThread()) {
-    NS_NOTREACHED("DataStorage::NotifyObservers called off main thread");
+    MOZ_ASSERT_UNREACHABLE("DataStorage::NotifyObservers called off main thread");
     return;
   }
 
@@ -854,12 +855,12 @@ DataStorage::ShutdownTimer()
 //------------------------------------------------------------
 
 NS_IMETHODIMP
-DataStorage::Observe(nsISupports* aSubject, const char* aTopic,
-                     const char16_t* aData)
+DataStorage::Observe(nsISupports* /*aSubject*/, const char* aTopic,
+                     const char16_t* /*aData*/)
 {
   // Don't access preferences off the main thread.
   if (!NS_IsMainThread()) {
-    NS_NOTREACHED("DataStorage::Observe called off main thread");
+    MOZ_ASSERT_UNREACHABLE("DataStorage::Observe called off main thread");
     return NS_ERROR_NOT_SAME_THREAD;
   }
 
diff --git a/security/manager/ssl/SSLServerCertVerification.cpp b/security/manager/ssl/SSLServerCertVerification.cpp
index bb965926ccd5..abe7a98fd00f 100644
--- a/security/manager/ssl/SSLServerCertVerification.cpp
+++ b/security/manager/ssl/SSLServerCertVerification.cpp
@@ -827,8 +827,7 @@ BlockServerCertChangeForSpdy(nsNSSSocketInfo* infoObject,
 
   status->GetServerCert(getter_AddRefs(cert));
   if (!cert) {
-    NS_NOTREACHED("every nsSSLStatus must have a cert"
-                  "that implements nsIX509Cert");
+    MOZ_ASSERT_UNREACHABLE("nsSSLStatus must have a cert implementing nsIX509Cert");
     PR_SetError(SEC_ERROR_LIBRARY_FAILURE, 0);
     return SECFailure;
   }
@@ -1567,7 +1566,7 @@ SSLServerCertVerificationJob::Run()
   }
 
   if (error == 0) {
-    NS_NOTREACHED("no error set during certificate validation failure");
+    MOZ_ASSERT_UNREACHABLE("No error set during certificate validation failure");
     error = PR_INVALID_STATE_ERROR;
   }
 
diff --git a/security/manager/ssl/nsCertOverrideService.cpp b/security/manager/ssl/nsCertOverrideService.cpp
index 1f6d172897ac..fd2f3a64c96a 100644
--- a/security/manager/ssl/nsCertOverrideService.cpp
+++ b/security/manager/ssl/nsCertOverrideService.cpp
@@ -100,7 +100,7 @@ nsresult
 nsCertOverrideService::Init()
 {
   if (!NS_IsMainThread()) {
-    NS_NOTREACHED("nsCertOverrideService initialized off main thread");
+    MOZ_ASSERT_UNREACHABLE("nsCertOverrideService initialized off main thread");
     return NS_ERROR_NOT_SAME_THREAD;
   }
 
diff --git a/security/manager/ssl/nsNSSCertificateFakeTransport.cpp b/security/manager/ssl/nsNSSCertificateFakeTransport.cpp
index 1a27b88bde4d..199794839547 100644
--- a/security/manager/ssl/nsNSSCertificateFakeTransport.cpp
+++ b/security/manager/ssl/nsNSSCertificateFakeTransport.cpp
@@ -31,147 +31,147 @@ nsNSSCertificateFakeTransport::~nsNSSCertificateFakeTransport()
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetDbKey(nsACString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetDisplayName(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetEmailAddress(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetEmailAddresses(uint32_t*, char16_t***)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::ContainsEmailAddress(const nsAString&, bool*)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetCommonName(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetOrganization(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetIssuerCommonName(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetIssuerOrganization(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetIssuerOrganizationUnit(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetIssuer(nsIX509Cert**)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetOrganizationalUnit(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetChain(nsIArray**)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetSubjectName(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetIssuerName(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetSerialNumber(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetSha256Fingerprint(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetSha1Fingerprint(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetTokenName(nsAString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetRawDER(uint32_t*, uint8_t**)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetValidity(nsIX509CertValidity**)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
@@ -185,21 +185,21 @@ nsNSSCertificateFakeTransport::GetKeyUsages(nsAString&)
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetASN1Structure(nsIASN1Object**)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::Equals(nsIX509Cert*, bool*)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetSha256SubjectPublicKeyInfoDigest(nsACString&)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
@@ -320,35 +320,35 @@ nsNSSCertificateFakeTransport::GetClassIDNoAlloc(nsCID* aClassIDNoAlloc)
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetCertType(unsigned int*)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetIsSelfSigned(bool*)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
-nsNSSCertificateFakeTransport::GetIsBuiltInRoot(bool* aIsBuiltInRoot)
+nsNSSCertificateFakeTransport::GetIsBuiltInRoot(bool*)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::GetAllTokenNames(unsigned int*, char16_t***)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 CERTCertificate*
 nsNSSCertificateFakeTransport::GetCert()
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return nullptr;
 }
 
@@ -357,14 +357,14 @@ nsNSSCertificateFakeTransport::ExportAsCMS(unsigned int,
                                            unsigned int*,
                                            unsigned char**)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertificateFakeTransport::MarkForPermDeletion()
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
@@ -389,35 +389,35 @@ nsNSSCertListFakeTransport::~nsNSSCertListFakeTransport()
 NS_IMETHODIMP
 nsNSSCertListFakeTransport::AddCert(nsIX509Cert* aCert)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertListFakeTransport::DeleteCert(nsIX509Cert* aCert)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 CERTCertList*
 nsNSSCertListFakeTransport::GetRawCertList()
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return nullptr;
 }
 
 NS_IMETHODIMP
 nsNSSCertListFakeTransport::GetEnumerator(nsISimpleEnumerator**)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 NS_IMETHODIMP
 nsNSSCertListFakeTransport::Equals(nsIX509CertList*, bool*)
 {
-  NS_NOTREACHED("Unimplemented on content process");
+  MOZ_ASSERT_UNREACHABLE("Unimplemented on content process");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
diff --git a/security/manager/ssl/nsNSSIOLayer.cpp b/security/manager/ssl/nsNSSIOLayer.cpp
index 9ee3180fee79..b4e6603afad1 100644
--- a/security/manager/ssl/nsNSSIOLayer.cpp
+++ b/security/manager/ssl/nsNSSIOLayer.cpp
@@ -1971,8 +1971,8 @@ nsNSS_SSLGetClientAuthData(void* arg, PRFileDesc* socket,
 
   UniqueCERTCertificate serverCert(SSL_PeerCertificate(socket));
   if (!serverCert) {
-    NS_NOTREACHED("Missing server certificate should have been detected during "
-                  "server cert authentication.");
+    MOZ_ASSERT_UNREACHABLE(
+      "Missing server cert should have been detected during server cert auth.");
     PR_SetError(SSL_ERROR_NO_CERTIFICATE, 0);
     return SECFailure;
   }
@@ -2315,12 +2315,12 @@ nsSSLIOLayerImportFD(PRFileDesc* fd,
   }
   if (SECSuccess != SSL_AuthCertificateHook(sslSock, AuthCertificateHook,
                                             infoObject)) {
-    NS_NOTREACHED("failed to configure AuthCertificateHook");
+    MOZ_ASSERT_UNREACHABLE("Failed to configure AuthCertificateHook");
     goto loser;
   }
 
   if (SECSuccess != SSL_SetURL(sslSock, host)) {
-    NS_NOTREACHED("SSL_SetURL failed");
+    MOZ_ASSERT_UNREACHABLE("SSL_SetURL failed");
     goto loser;
   }
 
diff --git a/security/manager/ssl/nsSecureBrowserUIImpl.cpp b/security/manager/ssl/nsSecureBrowserUIImpl.cpp
index e52c0e469622..3bb7652a5a00 100644
--- a/security/manager/ssl/nsSecureBrowserUIImpl.cpp
+++ b/security/manager/ssl/nsSecureBrowserUIImpl.cpp
@@ -334,15 +334,11 @@ static uint32_t GetSecurityStateFromSecurityInfoAndRequest(nsISupports* info,
 
 
 //  nsIWebProgressListener
-NS_IMETHODIMP 
-nsSecureBrowserUIImpl::OnProgressChange(nsIWebProgress* aWebProgress,
-                                        nsIRequest* aRequest,
-                                        int32_t aCurSelfProgress,
-                                        int32_t aMaxSelfProgress,
-                                        int32_t aCurTotalProgress,
-                                        int32_t aMaxTotalProgress)
+NS_IMETHODIMP
+nsSecureBrowserUIImpl::OnProgressChange(nsIWebProgress*, nsIRequest*, int32_t,
+                                        int32_t, int32_t, int32_t)
 {
-  NS_NOTREACHED("notification excluded in AddProgressListener(...)");
+  MOZ_ASSERT_UNREACHABLE("Should have been excluded in AddProgressListener()");
   return NS_OK;
 }
 
@@ -1132,12 +1128,10 @@ nsSecureBrowserUIImpl::OnLocationChange(nsIWebProgress* aWebProgress,
 }
 
 NS_IMETHODIMP
-nsSecureBrowserUIImpl::OnStatusChange(nsIWebProgress* aWebProgress,
-                                      nsIRequest* aRequest,
-                                      nsresult aStatus,
-                                      const char16_t* aMessage)
+nsSecureBrowserUIImpl::OnStatusChange(nsIWebProgress*, nsIRequest*, nsresult,
+                                      const char16_t*)
 {
-  NS_NOTREACHED("notification excluded in AddProgressListener(...)");
+  MOZ_ASSERT_UNREACHABLE("Should have been excluded in AddProgressListener()");
   return NS_OK;
 }
 
diff --git a/security/manager/ssl/nsSiteSecurityService.cpp b/security/manager/ssl/nsSiteSecurityService.cpp
index b3d26382c32b..7f09f5ffdc2e 100644
--- a/security/manager/ssl/nsSiteSecurityService.cpp
+++ b/security/manager/ssl/nsSiteSecurityService.cpp
@@ -228,7 +228,7 @@ nsSiteSecurityService::Init()
 {
   // Don't access Preferences off the main thread.
   if (!NS_IsMainThread()) {
-    NS_NOTREACHED("nsSiteSecurityService initialized off main thread");
+    MOZ_ASSERT_UNREACHABLE("nsSiteSecurityService initialized off main thread");
     return NS_ERROR_NOT_SAME_THREAD;
   }
 
@@ -1364,13 +1364,12 @@ nsSiteSecurityService::SetHPKPState(const char* aHost, SiteHPKPState& entry,
 //------------------------------------------------------------
 
 NS_IMETHODIMP
-nsSiteSecurityService::Observe(nsISupports *subject,
-                               const char *topic,
-                               const char16_t *data)
+nsSiteSecurityService::Observe(nsISupports* /*subject*/, const char* topic,
+                               const char16_t* /*data*/)
 {
   // Don't access Preferences off the main thread.
   if (!NS_IsMainThread()) {
-    NS_NOTREACHED("Preferences accessed off main thread");
+    MOZ_ASSERT_UNREACHABLE("Preferences accessed off main thread");
     return NS_ERROR_NOT_SAME_THREAD;
   }