diff --git a/miasm/core/cpu.py b/miasm/core/cpu.py
index dae93bf9c..7df9f9919 100644
--- a/miasm/core/cpu.py
+++ b/miasm/core/cpu.py
@@ -393,7 +393,7 @@ def cb_op_mul(tokens):
 variable.setParseAction(cb_parse_id)
 operand = str_int | variable
 
-base_expr = pyparsing.operatorPrecedence(operand,
+base_expr = pyparsing.infixNotation(operand,
                                [(notop,   1, pyparsing.opAssoc.RIGHT, cb_op_not),
                                 (andop, 2, pyparsing.opAssoc.RIGHT, cb_op_and),
                                 (xorop, 2, pyparsing.opAssoc.RIGHT, cb_op_xor),
diff --git a/requirements.txt b/requirements.txt
index 5db3c2a8f..b518400d0 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,2 +1,2 @@
-pyparsing~=2.0
+pyparsing>=2.4.1
 future
diff --git a/setup.py b/setup.py
index a33f608fc..e1e544340 100644
--- a/setup.py
+++ b/setup.py
@@ -325,7 +325,7 @@ def build_all():
                         "VERSION"
                     ]
                 },
-                install_requires=["future", "pyparsing~=2.0"],
+                install_requires=["future", "pyparsing>=2.4.1"],
                 cmdclass={"install_data": smart_install_data},
                 ext_modules = ext_modules,
                 # Metadata