Index: src/prelude/builtins.c
===================================================================
--- src/prelude/builtins.c	(revision 2a8427c61128cfaed539e695bd10d0c71b358737)
+++ src/prelude/builtins.c	(revision 8f13c98e3b81021a6d2d3197832eb1cb7c5339df)
@@ -23,4 +23,18 @@
 void exit( int status, const char fmt[], ... ) __attribute__ (( format(printf, 2, 3), __nothrow__, __leaf__, __noreturn__ ));
 void abort ( const char fmt[], ... ) __attribute__ (( format(printf, 1, 2), __nothrow__, __leaf__, __noreturn__ ));
+
+// increment/decrement unification
+
+static inline forall( dtype T | { T& ?+=?( T&, one_t ); } )
+T& ++? ( T& x ) { return x += 1; }
+
+static inline forall( dtype T | sized(T) | { void ?{}( T&, T ); void ^?{}( T& ); T& ?+=?( T&, one_t ); } )
+T& ?++ ( T& x ) { T tmp = x; x += 1; return tmp; }
+
+static inline forall( dtype T | { T& ?-=?( T&, one_t ); } )
+T& --? ( T& x ) { return x -= 1; }
+
+static inline forall( dtype T | sized(T) | { void ?{}( T&, T ); void ^?{}( T& ); T& ?-=?( T&, one_t ); } )
+T& ?-- ( T& x ) { T tmp = x; x -= 1; return tmp; }
 
 // exponentiation operator implementation
Index: src/tests/.expect/counter.txt
===================================================================
--- src/tests/.expect/counter.txt	(revision 8f13c98e3b81021a6d2d3197832eb1cb7c5339df)
+++ src/tests/.expect/counter.txt	(revision 8f13c98e3b81021a6d2d3197832eb1cb7c5339df)
@@ -0,0 +1,2 @@
+45
+42
Index: src/tests/counter.c
===================================================================
--- src/tests/counter.c	(revision 8f13c98e3b81021a6d2d3197832eb1cb7c5339df)
+++ src/tests/counter.c	(revision 8f13c98e3b81021a6d2d3197832eb1cb7c5339df)
@@ -0,0 +1,40 @@
+// 
+// Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
+//
+// The contents of this file are covered under the licence agreement in the
+// file "LICENCE" distributed with Cforall.
+// 
+// counter.c -- 
+// 
+// Author           : Aaron B. Moss
+// Created On       : Thu Feb 22 15:27:00 2018
+// Last Modified By : Aaron B. Moss
+// Last Modified On : Thu Feb 22 15:27:00 2018
+// Update Count     : 1
+// 
+
+// Tests unified increment/decrement builtin functions.
+// Could be extended for other arithmetic unifications
+
+struct counter { int x; };
+
+counter& ?+=?( counter& c, one_t ) { ++c.x; return c; }
+
+counter& ?-=?( counter& c, one_t ) { --c.x; return c; }
+
+int main() {
+    counter c = { 42 };
+    c += 1;
+    ++c;
+    c++;
+    printf("%d\n", c.x);
+    c -= 1;
+    --c;
+    c--;
+    printf("%d\n", c.x);
+}
+
+// Local Variables: //
+// tab-width: 4 //
+// compile-command: "cfa counter.c" //
+// End: //