diff --git a/HISTORY.rst b/HISTORY.rst
index 481b1970..3241cca9 100644
--- a/HISTORY.rst
+++ b/HISTORY.rst
@@ -76,7 +76,8 @@ PlatformIO 3.0
   ``-v, --verbose`` option
   (`issue #721 <https://github.com/platformio/platformio/issues/721>`_)
 * Improved INO to CPP converter
-  (`issue #659 <https://github.com/platformio/platformio/issues/659>`_)
+  (`issue #659 <https://github.com/platformio/platformio/issues/659>`_,
+   `issue #765 <https://github.com/platformio/platformio/issues/765>`_)
 * Added ``license`` field to `library.json <http://docs.platformio.org/en/latest/librarymanager/config.html>`__
   (`issue #522 <https://github.com/platformio/platformio/issues/522>`_)
 * Warn about unknown options in project configuration file ``platformio.ini``
diff --git a/platformio/__init__.py b/platformio/__init__.py
index 5c776f68..a813278b 100644
--- a/platformio/__init__.py
+++ b/platformio/__init__.py
@@ -14,7 +14,7 @@
 
 import sys
 
-VERSION = (3, 0, "0b7")
+VERSION = (3, 0, "0b8")
 __version__ = ".".join([str(s) for s in VERSION])
 
 __title__ = "platformio"
diff --git a/platformio/builder/tools/piomisc.py b/platformio/builder/tools/piomisc.py
index 75f748a5..1a6d83c9 100644
--- a/platformio/builder/tools/piomisc.py
+++ b/platformio/builder/tools/piomisc.py
@@ -72,6 +72,7 @@ class InoToCPPConverter(object):
         assert self._gcc_preprocess(contents, out_file)
         with open(out_file) as fp:
             contents = fp.read()
+        contents = self._join_multiline_strings(contents)
         with open(out_file, "w") as fp:
             fp.write(self.append_prototypes(contents))
         return out_file
@@ -89,6 +90,45 @@ class InoToCPPConverter(object):
         atexit.register(_delete_file, tmp_path)
         return isfile(out_file)
 
+    def _join_multiline_strings(self, contents):
+        if "\\" not in contents:
+            return contents
+        newlines = []
+        linenum = 0
+        stropen = False
+        for line in contents.split("\n"):
+            _linenum = self._parse_preproc_line_num(line)
+            if _linenum is not None:
+                linenum = _linenum
+                continue
+            else:
+                linenum += 1
+
+            if line.endswith("\\"):
+                if line.startswith('"'):
+                    newlines.append(line[:-1])
+                    stropen = True
+                elif stropen:
+                    newlines[len(newlines) - 1] += line[:-1]
+            elif stropen and line.endswith('";'):
+                newlines[len(newlines) - 1] += line
+                stropen = False
+                newlines.append('#line %d "%s"' %
+                                (linenum, self._main_ino.replace("\\", "/")))
+            else:
+                newlines.append(line)
+
+        return "\n".join(newlines)
+
+    @staticmethod
+    def _parse_preproc_line_num(line):
+        if not line.startswith("#"):
+            return None
+        tokens = line.split(" ", 3)
+        if len(tokens) > 2 and tokens[1].isdigit():
+            return int(tokens[1])
+        return None
+
     def _parse_prototypes(self, contents):
         prototypes = []
         reserved_keywords = set(["if", "else", "while"])
@@ -99,14 +139,12 @@ class InoToCPPConverter(object):
             prototypes.append(match)
         return prototypes
 
-    @staticmethod
-    def _get_total_lines(contents):
+    def _get_total_lines(self, contents):
         total = 0
         for line in contents.split("\n")[::-1]:
-            if line.startswith("#"):
-                tokens = line.split(" ", 3)
-                if len(tokens) > 2 and tokens[1].isdigit():
-                    return int(tokens[1]) + total
+            linenum = self._parse_preproc_line_num(line)
+            if linenum is not None:
+                return total + linenum
             total += 1
         return total
 
diff --git a/tests/ino2cpp/strmultilines/main.ino b/tests/ino2cpp/strmultilines/main.ino
new file mode 100644
index 00000000..c5df8f30
--- /dev/null
+++ b/tests/ino2cpp/strmultilines/main.ino
@@ -0,0 +1,79 @@
+const char headerEndP[] PROGMEM =
+"<meta name='viewport' content='width=device-width, initial-scale=1'>\
+<link rel='stylesheet' href='http://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css'>\
+<script src='https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js'></script>\
+<script src='http://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js'></script></head>";
+
+void setup() {
+
+}
+
+const char javaScriptPinControlP[] PROGMEM =
+"<div id='content'></div>\
+<div id='pin1'></div>\
+<script>\
+function show()\
+{\
+$.ajax({\
+url: 'controlstatus',\
+cache: false,\
+success: function(html){\
+$('#content').html(html);\
+}\
+});\
+}\
+function Pin1()\
+{\
+$.ajax({\
+type: 'POST',\
+url: 'control',\
+data: '1=1',\
+success: function(data){\
+show();\
+}\
+});\
+}\
+function Auto1()\
+{\
+$.ajax({\
+type: 'POST',\
+url: 'control',\
+data: '1=2',\
+success: function(data){\
+show();\
+}\
+});\
+}\
+function Pin2()\
+{\
+$.ajax({\
+type: 'POST',\
+url: 'control',\
+data: '2=1',\
+success: function(data){\
+show();\
+}\
+});\
+}\
+function Auto2()\
+{\
+$.ajax({\
+type: 'POST',\
+url: 'control',\
+data: '2=2',\
+success: function(data){\
+show();\
+}\
+});\
+}\
+$(document).ready(function(){\
+show();\
+setInterval('show()',5000);\
+});\
+</script>";
+
+#warning "Line 75"
+
+void loop() {
+
+}
\ No newline at end of file
diff --git a/tests/test_ino2cpp.py b/tests/test_ino2cpp.py
index 0bb6b143..d4008628 100644
--- a/tests/test_ino2cpp.py
+++ b/tests/test_ino2cpp.py
@@ -42,3 +42,7 @@ def test_warning_line(clirunner, validate_cliresult):
     validate_cliresult(result)
     assert ('basic.ino:13:14: warning: #warning "Line number is 13"' in
             result.output)
+    result = clirunner.invoke(
+        cmd_ci, [join(INOTEST_DIR, "strmultilines"), "-b", "uno"])
+    validate_cliresult(result)
+    assert ('main.ino:75:2: warning: #warning "Line 75"' in result.output)