diff --git a/t/t4034/cpp/expect b/t/t4034/cpp/expect
index 63e53a61e6..46c9460a96 100644
--- a/t/t4034/cpp/expect
+++ b/t/t4034/cpp/expect
@@ -3,24 +3,24 @@
 <BOLD>--- a/pre<RESET>
 <BOLD>+++ b/post<RESET>
 <CYAN>@@ -1,30 +1,30 @@<RESET>
-Foo() : x(0<RED>&&1<RESET><GREEN>&42<RESET>) { <RED>foo0<RESET><GREEN>bar<RESET>(x<RED>.f<RESET><GREEN>.F<RESET>ind); }
+Foo() : x(0<RED>&&1<RESET><GREEN>&42<RESET>) { <RED>foo0<RESET><GREEN>bar<RESET>(x.<RED>find<RESET><GREEN>Find<RESET>); }
 cout<<"Hello World<RED>!<RESET><GREEN>?<RESET>\n"<<endl;
-<GREEN>(<RESET>1 <RED>-1e10<RESET><GREEN>+1e10<RESET> 0xabcdef<GREEN>)<RESET> '<RED>x<RESET><GREEN>y<RESET>'
+<GREEN>(<RESET>1 <RED>-<RESET><GREEN>+<RESET>1e10 0xabcdef<GREEN>)<RESET> '<RED>x<RESET><GREEN>y<RESET>'
 // long double<RESET>
 <RED>3.141592653e-10l<RESET><GREEN>3.141592654e+10l<RESET>
 // float<RESET>
-120<RED>E5f<RESET><GREEN>E6f<RESET>
+<RED>120E5f<RESET><GREEN>120E6f<RESET>
 // hex<RESET>
-<RED>0xdeadbeaf+8<RESET><GREEN>0xdeadBeaf+7<RESET>ULL
+<RED>0xdeadbeaf<RESET><GREEN>0xdeadBeaf<RESET>+<RED>8ULL<RESET><GREEN>7ULL<RESET>
 // octal<RESET>
 <RED>01234567<RESET><GREEN>01234560<RESET>
 // binary<RESET>
 <RED>0b1000<RESET><GREEN>0b1100<RESET>+e1
 // expression<RESET>
-<RED>1.5-e+2+f<RESET><GREEN>1.5-e+3+f<RESET>
+1.5-e+<RED>2<RESET><GREEN>3<RESET>+f
 // another one<RESET>
-str<RED>.e+65<RESET><GREEN>.e+75<RESET>
-[a] b<RED>-><RESET><GREEN>->*<RESET>v d<RED>.e<RESET><GREEN>.*e<RESET>
+str.e+<RED>65<RESET><GREEN>75<RESET>
+[a] b<RED>-><RESET><GREEN>->*<RESET>v d<RED>.<RESET><GREEN>.*<RESET>e
 <GREEN>~<RESET>!a <GREEN>!<RESET>~b c<RED>++<RESET><GREEN>+<RESET> d<RED>--<RESET><GREEN>-<RESET> e*<GREEN>*<RESET>f g<RED>&<RESET><GREEN>&&<RESET>h
 a<RED>*<RESET><GREEN>*=<RESET>b c<RED>/<RESET><GREEN>/=<RESET>d e<RED>%<RESET><GREEN>%=<RESET>f
 a<RED>+<RESET><GREEN>++<RESET>b c<RED>-<RESET><GREEN>--<RESET>d
@@ -30,6 +30,6 @@ a<RED>==<RESET><GREEN>!=<RESET>b c<RED>!=<RESET><GREEN>=<RESET>d
 a<RED>^<RESET><GREEN>^=<RESET>b c<RED>|<RESET><GREEN>|=<RESET>d e<RED>&&<RESET><GREEN>&=<RESET>f
 a<RED>||<RESET><GREEN>|<RESET>b
 a?<GREEN>:<RESET>b
-a<RED>=<RESET><GREEN>==<RESET>b c<RED>+=<RESET><GREEN>+<RESET>d <RED>e-=f<RESET><GREEN>e-f<RESET> g<RED>*=<RESET><GREEN>*<RESET>h i<RED>/=<RESET><GREEN>/<RESET>j k<RED>%=<RESET><GREEN>%<RESET>l m<RED><<=<RESET><GREEN><<<RESET>n o<RED>>>=<RESET><GREEN>>><RESET>p q<RED>&=<RESET><GREEN>&<RESET>r s<RED>^=<RESET><GREEN>^<RESET>t u<RED>|=<RESET><GREEN>|<RESET>v
+a<RED>=<RESET><GREEN>==<RESET>b c<RED>+=<RESET><GREEN>+<RESET>d e<RED>-=<RESET><GREEN>-<RESET>f g<RED>*=<RESET><GREEN>*<RESET>h i<RED>/=<RESET><GREEN>/<RESET>j k<RED>%=<RESET><GREEN>%<RESET>l m<RED><<=<RESET><GREEN><<<RESET>n o<RED>>>=<RESET><GREEN>>><RESET>p q<RED>&=<RESET><GREEN>&<RESET>r s<RED>^=<RESET><GREEN>^<RESET>t u<RED>|=<RESET><GREEN>|<RESET>v
 a,b<RESET>
 a<RED>::<RESET><GREEN>:<RESET>b
diff --git a/userdiff.c b/userdiff.c
index af02b1878c..8b49194f56 100644
--- a/userdiff.c
+++ b/userdiff.c
@@ -64,8 +64,14 @@ PATTERNS("cpp",
 	 /* functions/methods, variables, and compounds at top level */
 	 "^((::[[:space:]]*)?[A-Za-z_].*)$",
 	 /* -- */
+	 /* identifiers and keywords */
 	 "[a-zA-Z_][a-zA-Z0-9_]*"
-	 "|[-+0-9.e]+[fFlL]?|0[xXbB]?[0-9a-fA-F]+[lLuU]*"
+	 /* decimal and octal integers as well as floatingpoint numbers */
+	 "|[0-9][0-9.]*([Ee][-+]?[0-9]+)?[fFlLuU]*"
+	 /* hexadecimal and binary integers */
+	 "|0[xXbB][0-9a-fA-F]+[lLuU]*"
+	 /* floatingpoint numbers that begin with a decimal point */
+	 "|\\.[0-9]+([Ee][-+]?[0-9]+)?[fFlL]?"
 	 "|[-+*/<>%&^|=!]=|--|\\+\\+|<<=?|>>=?|&&|\\|\\||::|->\\*?|\\.\\*"),
 PATTERNS("csharp",
 	 /* Keywords */