diff --git a/config_gen.py b/config_gen.py
index c282026..ee10a6f 100755
--- a/config_gen.py
+++ b/config_gen.py
@@ -323,7 +323,8 @@ def parse_flags(build_log):
 
     # macro definitions should be handled separately, so we can resolve duplicates
     define_flags = dict()
-    define_regex = re.compile("-D([a-zA-Z0-9_]+)=(.*)")
+    define_regex = re.compile("-D\s*([a-zA-Z0-9_]+)(=.*)?")
+    define_flag = '-D'
 
     # Used to only bundle filenames with applicable arguments
     filename_flags = ["-o", "-I", "-isystem", "-include", "-imacros", "-isysroot"]
@@ -337,8 +338,12 @@ def parse_flags(build_log):
         line_count += 1
         words = split_flags(line)
 
+        cmd_pwd = './'
+
         for (i, word) in enumerate(words):
             if(word[0] != '-' or not flags_whitelist.match(word)):
+                if(word.find('YCM_CONFIG_GEN_PWD') == 0):
+                    cmd_pwd = word[word.find("=") + 1:]
                 continue
 
             # handle macro definitions
@@ -351,9 +356,13 @@ def parse_flags(build_log):
 
                 continue
 
+            if(word == define_flag):
+                flags.add(word + words[i+1])
+                continue
+
             # include arguments for this option, if there are any, as a tuple
             if(i != len(words) - 1 and word in filename_flags and words[i + 1][0] != '-'):
-                flags.add((word, words[i + 1]))
+                flags.add((word, os.path.realpath(os.path.join(cmd_pwd, words[i + 1]))))
             else:
                 flags.add(word)
 
@@ -374,7 +383,10 @@ def parse_flags(build_log):
             print("WARNING: {} distinct definitions of macro {} found".format(len(values), name))
             values.sort()
 
-        flags.add("-D{}={}".format(name, values[0]))
+        if values[0] != None:
+            flags.add("-D{}{}".format(name, values[0]))
+        else:
+            flags.add("-D{}".format(name))
 
     return (line_count, skip_count, sorted(flags))
 
diff --git a/fake-toolchain/Unix/cc b/fake-toolchain/Unix/cc
index 9a321b6..4c52fcd 100755
--- a/fake-toolchain/Unix/cc
+++ b/fake-toolchain/Unix/cc
@@ -9,6 +9,6 @@ elif [ "$1" = "-v" ] || [ "$1" = "--version" ]; then
     $YCM_CONFIG_GEN_CC_PASSTHROUGH $@
 
 else
-    echo "$@" >> $YCM_CONFIG_GEN_CC_LOG
+	echo "YCM_CONFIG_GEN_PWD=$(pwd) $@" >> $YCM_CONFIG_GEN_CC_LOG
 fi