diff --git a/.travis.yml b/.travis.yml
index 7078fd092..8f871c09a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -43,12 +43,15 @@ matrix:
   - os: linux
     compiler: clang
     env:
-      - COMPILER=clang++-5.0
+      - COMPILER=clang++-7
       - CMAKE_OPTIONS=-DJSON_Sanitizer=ON
+      - UBSAN_OPTIONS=print_stacktrace=1,suppressions=$(pwd)/test/src/UBSAN.supp
     addons:
       apt:
-        sources: ['ubuntu-toolchain-r-test', 'llvm-toolchain-trusty-5.0']
-        packages: ['g++-6', 'clang-5.0', 'ninja-build']
+        sources: ['ubuntu-toolchain-r-test', 'llvm-toolchain-trusty-7']
+        packages: ['g++-6', 'clang-7', 'ninja-build']
+    before_script:
+      - export PATH=$PATH:/usr/lib/llvm-7/bin
 
   # cppcheck
   - os: linux
@@ -330,7 +333,7 @@ script:
   # compile and execute unit tests
   - mkdir -p build && cd build
   - cmake .. ${CMAKE_OPTIONS} -DJSON_MultipleHeaders=${MULTIPLE_HEADERS} -GNinja && cmake --build . --config Release
-  - ctest -C Release -V -j
+  - ctest -C Release --timeout 2700 -V -j
   - cd ..
 
   # check if homebrew works (only checks develop branch)   
diff --git a/include/nlohmann/detail/conversions/to_json.hpp b/include/nlohmann/detail/conversions/to_json.hpp
index db9eaf2bd..c3ac5aa8f 100644
--- a/include/nlohmann/detail/conversions/to_json.hpp
+++ b/include/nlohmann/detail/conversions/to_json.hpp
@@ -154,7 +154,10 @@ struct external_constructor<value_t::array>
         j.m_type = value_t::array;
         j.m_value = value_t::array;
         j.m_value.array->resize(arr.size());
-        std::copy(std::begin(arr), std::end(arr), j.m_value.array->begin());
+        if (arr.size() > 0)
+        {
+            std::copy(std::begin(arr), std::end(arr), j.m_value.array->begin());
+        }
         j.assert_invariant();
     }
 };
diff --git a/include/nlohmann/detail/input/input_adapters.hpp b/include/nlohmann/detail/input/input_adapters.hpp
index b7b11de03..9512a771e 100644
--- a/include/nlohmann/detail/input/input_adapters.hpp
+++ b/include/nlohmann/detail/input/input_adapters.hpp
@@ -131,9 +131,8 @@ class input_stream_adapter : public input_adapter_protocol
 class input_buffer_adapter : public input_adapter_protocol
 {
   public:
-    JSON_HEDLEY_NON_NULL(2)
     input_buffer_adapter(const char* b, const std::size_t l) noexcept
-        : cursor(b), limit(b + l)
+        : cursor(b), limit(b == nullptr ? nullptr : (b + l))
     {}
 
     // delete because of pointer members
@@ -147,6 +146,7 @@ class input_buffer_adapter : public input_adapter_protocol
     {
         if (JSON_HEDLEY_LIKELY(cursor < limit))
         {
+            assert(cursor != nullptr and limit != nullptr);
             return std::char_traits<char>::to_int_type(*(cursor++));
         }
 
diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp
index 2a32a8296..e54c3e41f 100644
--- a/single_include/nlohmann/json.hpp
+++ b/single_include/nlohmann/json.hpp
@@ -3489,7 +3489,10 @@ struct external_constructor<value_t::array>
         j.m_type = value_t::array;
         j.m_value = value_t::array;
         j.m_value.array->resize(arr.size());
-        std::copy(std::begin(arr), std::end(arr), j.m_value.array->begin());
+        if (arr.size() > 0)
+        {
+            std::copy(std::begin(arr), std::end(arr), j.m_value.array->begin());
+        }
         j.assert_invariant();
     }
 };
@@ -3882,9 +3885,8 @@ class input_stream_adapter : public input_adapter_protocol
 class input_buffer_adapter : public input_adapter_protocol
 {
   public:
-    JSON_HEDLEY_NON_NULL(2)
     input_buffer_adapter(const char* b, const std::size_t l) noexcept
-        : cursor(b), limit(b + l)
+        : cursor(b), limit(b == nullptr ? nullptr : (b + l))
     {}
 
     // delete because of pointer members
@@ -3898,6 +3900,7 @@ class input_buffer_adapter : public input_adapter_protocol
     {
         if (JSON_HEDLEY_LIKELY(cursor < limit))
         {
+            assert(cursor != nullptr and limit != nullptr);
             return std::char_traits<char>::to_int_type(*(cursor++));
         }
 
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index b73dfc9ad..e13d31bba 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -6,7 +6,7 @@ option(JSON_Coverage "Build test suite with coverage information" OFF)
 if(JSON_Sanitizer)
     message(STATUS "Building test suite with Clang sanitizer")
     if(NOT MSVC)
-        set(CMAKE_CXX_FLAGS "-g -O2 -fsanitize=address -fsanitize=undefined -fsanitize=integer -fsanitize=nullability -fno-omit-frame-pointer")
+        set(CMAKE_CXX_FLAGS "-g -O0 -fsanitize=address -fsanitize=undefined -fsanitize=integer -fsanitize=nullability -fno-omit-frame-pointer -fno-sanitize-recover=all -fsanitize-recover=unsigned-integer-overflow")
     endif()
 endif()
 
@@ -71,7 +71,7 @@ set_target_properties(doctest_main PROPERTIES
     COMPILE_DEFINITIONS "$<$<CXX_COMPILER_ID:MSVC>:_SCL_SECURE_NO_WARNINGS>"
     COMPILE_OPTIONS "$<$<CXX_COMPILER_ID:MSVC>:/EHsc;$<$<CONFIG:Release>:/Od>>"
 )
-if (${CMAKE_VERSION} VERSION_LESS "3.8.0") 
+if (${CMAKE_VERSION} VERSION_LESS "3.8.0")
     target_compile_features(doctest_main PUBLIC cxx_range_for)
 else()
     target_compile_features(doctest_main PUBLIC cxx_std_11)
@@ -92,7 +92,7 @@ if(MSVC)
 	# Disable warning C4566: character represented by universal-character-name '\uFF01' cannot be represented in the current code page (1252)
 	# Disable warning C4996: 'nlohmann::basic_json<std::map,std::vector,std::string,bool,int64_t,uint64_t,double,std::allocator,nlohmann::adl_serializer>::operator <<': was declared deprecated
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /wd4389 /wd4309 /wd4566 /wd4996")
-	
+
 	# https://github.com/nlohmann/json/issues/1114
 	set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} /bigobj")
 endif()
diff --git a/test/src/UBSAN.supp b/test/src/UBSAN.supp
new file mode 100644
index 000000000..b19f04369
--- /dev/null
+++ b/test/src/UBSAN.supp
@@ -0,0 +1 @@
+unsigned-integer-overflow:stl_bvector.h