diff --git a/cpp/ql/test/library-tests/regex/parse.expected b/cpp/ql/test/library-tests/regex/parse.expected
index 2224556cd52..0f07ba72809 100644
--- a/cpp/ql/test/library-tests/regex/parse.expected
+++ b/cpp/ql/test/library-tests/regex/parse.expected
@@ -26,6 +26,14 @@
 
 #-----| [RegExpConstant, RegExpNormalChar] b
 
+#-----| [RegExpConstant, RegExpEscape] \c
+
+#-----| [RegExpConstant, RegExpNormalChar] Z
+
+#-----| [RegExpConstant, RegExpEscape] \c
+
+#-----| [RegExpConstant, RegExpNormalChar] A
+
 #-----| [RegExpConstant, RegExpEscape] \u{987
 
 #-----| [RegExpConstant, RegExpNormalChar] A
@@ -163,6 +171,10 @@
 #-----| 1 -> [RegExpConstant, RegExpEscape] \n
 #-----| 2 -> [RegExpConstant, RegExpNormalChar] b
 
+#-----| [RegExpSequence] \cA
+#-----| 0 -> [RegExpConstant, RegExpEscape] \c
+#-----| 1 -> [RegExpConstant, RegExpNormalChar] A
+
 #-----| [RegExpSequence] [[:alpha:]][[:digit:]]
 #-----| 0 -> [RegExpCharacterClass] [[:alpha:]]
 #-----| 1 -> [RegExpCharacterClass] [[:digit:]]
@@ -279,6 +291,10 @@
 #-----| 0 -> [RegExpConstant, RegExpNormalChar] 0
 #-----| 1 -> [RegExpConstant, RegExpNormalChar] 9
 
+#-----| [RegExpCharacterClass] [\cZ]
+#-----| 0 -> [RegExpConstant, RegExpEscape] \c
+#-----| 1 -> [RegExpConstant, RegExpNormalChar] Z
+
 #-----| [RegExpCharacterClass] [A-F[:digit:]a-f]
 #-----| 0 -> [RegExpCharacterRange] A-F
 
diff --git a/cpp/ql/test/library-tests/regex/regexp.cpp b/cpp/ql/test/library-tests/regex/regexp.cpp
index 3f8330a0a59..86352695dc5 100644
--- a/cpp/ql/test/library-tests/regex/regexp.cpp
+++ b/cpp/ql/test/library-tests/regex/regexp.cpp
@@ -76,6 +76,10 @@ std::regex r_posix4("[:digit:]");
 // unicode
 std::regex r_uni("\\u{9879}");
 
+// control escapes
+std::regex r_ctrl1("\\cA");
+std::regex r_ctrl2("[\\cZ]");
+
 // String literal spellings for location tests
 std::regex r_loc_plain("a\\nb");
 std::basic_regex<wchar_t> r_loc_L(L"abc");
diff --git a/cpp/ql/test/library-tests/regex/regexp.expected b/cpp/ql/test/library-tests/regex/regexp.expected
index ddac96dd553..3f3c8b64604 100644
--- a/cpp/ql/test/library-tests/regex/regexp.expected
+++ b/cpp/ql/test/library-tests/regex/regexp.expected
@@ -32,6 +32,7 @@ term
 | file://:0:0:0:0 | A | RegExpConstant,RegExpNormalChar |
 | file://:0:0:0:0 | A | RegExpConstant,RegExpNormalChar |
 | file://:0:0:0:0 | A | RegExpConstant,RegExpNormalChar |
+| file://:0:0:0:0 | A | RegExpConstant,RegExpNormalChar |
 | file://:0:0:0:0 | A-F | RegExpCharacterRange |
 | file://:0:0:0:0 | A-F | RegExpCharacterRange |
 | file://:0:0:0:0 | A-F] | RegExpConstant,RegExpNormalChar |
@@ -39,6 +40,7 @@ term
 | file://:0:0:0:0 | F | RegExpConstant,RegExpNormalChar |
 | file://:0:0:0:0 | F | RegExpConstant,RegExpNormalChar |
 | file://:0:0:0:0 | Z | RegExpConstant,RegExpNormalChar |
+| file://:0:0:0:0 | Z | RegExpConstant,RegExpNormalChar |
 | file://:0:0:0:0 | [ | RegExpConstant,RegExpNormalChar |
 | file://:0:0:0:0 | [123] | RegExpCharacterClass |
 | file://:0:0:0:0 | [A-F[:digit:]a-f] | RegExpCharacterClass |
@@ -48,6 +50,7 @@ term
 | file://:0:0:0:0 | [[:digit:]] | RegExpCharacterClass |
 | file://:0:0:0:0 | [[a-f] | RegExpCharacterClass |
 | file://:0:0:0:0 | [[a-f]A-F] | RegExpSequence |
+| file://:0:0:0:0 | [\\cZ] | RegExpCharacterClass |
 | file://:0:0:0:0 | [\\w] | RegExpCharacterClass |
 | file://:0:0:0:0 | [\\w]+ | RegExpPlus |
 | file://:0:0:0:0 | [\|] | RegExpCharacterClass |
@@ -67,6 +70,9 @@ term
 | file://:0:0:0:0 | \\] | RegExpConstant,RegExpEscape |
 | file://:0:0:0:0 | \\b | RegExpSpecialChar |
 | file://:0:0:0:0 | \\b!a\\B | RegExpSequence |
+| file://:0:0:0:0 | \\c | RegExpConstant,RegExpEscape |
+| file://:0:0:0:0 | \\c | RegExpConstant,RegExpEscape |
+| file://:0:0:0:0 | \\cA | RegExpSequence |
 | file://:0:0:0:0 | \\d | RegExpCharacterClassEscape |
 | file://:0:0:0:0 | \\d\\D | RegExpSequence |
 | file://:0:0:0:0 | \\n | RegExpConstant,RegExpEscape |
@@ -161,16 +167,20 @@ regExpNormalCharValue
 | file://:0:0:0:0 | A | A |
 | file://:0:0:0:0 | A | A |
 | file://:0:0:0:0 | A | A |
+| file://:0:0:0:0 | A | A |
 | file://:0:0:0:0 | A-F] | A-F] |
 | file://:0:0:0:0 | F | F |
 | file://:0:0:0:0 | F | F |
 | file://:0:0:0:0 | Z | Z |
+| file://:0:0:0:0 | Z | Z |
 | file://:0:0:0:0 | [ | [ |
 | file://:0:0:0:0 | \\D | D |
 | file://:0:0:0:0 | \\S | S |
 | file://:0:0:0:0 | \\W | W |
 | file://:0:0:0:0 | \\[ | [ |
 | file://:0:0:0:0 | \\] | ] |
+| file://:0:0:0:0 | \\c | c |
+| file://:0:0:0:0 | \\c | c |
 | file://:0:0:0:0 | \\d | d |
 | file://:0:0:0:0 | \\n | \n |
 | file://:0:0:0:0 | \\n | \n |