diff --git a/core/src/main/java/org/lflang/generator/c/CGenerator.java b/core/src/main/java/org/lflang/generator/c/CGenerator.java
index c493744a4c..e3955d63df 100644
--- a/core/src/main/java/org/lflang/generator/c/CGenerator.java
+++ b/core/src/main/java/org/lflang/generator/c/CGenerator.java
@@ -986,7 +986,6 @@ protected void generateReactorClassHeaders(
     }
     header.pr("#include \"include/core/reactor.h\"");
     src.pr("#include \"include/api/api.h\"");
-    src.pr("#include \"include/api/set.h\"");
     generateIncludes(tpr);
     if (CCppMode) {
       src.pr("}");
diff --git a/core/src/main/java/org/lflang/generator/c/CReactorHeaderFileGenerator.java b/core/src/main/java/org/lflang/generator/c/CReactorHeaderFileGenerator.java
index 5deaa5fb7b..ced74cb160 100644
--- a/core/src/main/java/org/lflang/generator/c/CReactorHeaderFileGenerator.java
+++ b/core/src/main/java/org/lflang/generator/c/CReactorHeaderFileGenerator.java
@@ -81,7 +81,6 @@ private static void appendPoundIncludes(CodeBuilder builder) {
             extern "C" {
             #endif
             #include "../include/api/api.h"
-            #include "../include/api/set.h"
             #include "../include/core/reactor.h"
             #ifdef __cplusplus
             }
diff --git a/core/src/main/resources/lib/c/reactor-c b/core/src/main/resources/lib/c/reactor-c
index 294fbb2ad7..ac3f64993d 160000
--- a/core/src/main/resources/lib/c/reactor-c
+++ b/core/src/main/resources/lib/c/reactor-c
@@ -1 +1 @@
-Subproject commit 294fbb2ad72648bbae204ce9c62ce5d2b1c9e12d
+Subproject commit ac3f64993d40d8db2ee5e3af3fb10cbb8035b7c1