diff --git a/master.cfg b/master.cfg
index fe0a53f..8297112 100644
--- a/master.cfg
+++ b/master.cfg
@@ -565,18 +565,22 @@ class RunTestGDBIndexBuild (BuildAndTestGDBFactory):
 
 class RunTestGDBPlainBSD_c64t64 (RunTestGDBPlain_c64t64):
     """Compiling for 64-bit, testing on 64-bit."""
+    extra_conf_flags = [ 'CFLAGS=-I/usr/local/include' ]
     make_command = 'gmake'
 
 class RunTestGDBNativeGDBServerBSD_c64t64 (RunTestGDBNativeGDBServer_c64t64):
     """Compiling on 64-bit, testing native-gdbserver on 64-bit."""
+    extra_conf_flags = [ 'CFLAGS=-I/usr/local/include' ]
     make_command = 'gmake'
 
 class RunTestGDBNativeExtendedGDBServerBSD_c64t64 (RunTestGDBNativeExtendedGDBServer_c64t64):
     """Compiling on 64-bit, testing native-extended-gdbserver on 64-bit."""
+    extra_conf_flags = [ 'CFLAGS=-I/usr/local/include' ]
     make_command = 'gmake'
 
 class RunTestGDBIndexBuildBSD (RunTestGDBIndexBuild):
     """Testing with the "cc-with-tweaks.sh" passing -i.  FIXME: include bitness here."""
+    extra_conf_flags = [ 'CFLAGS=-I/usr/local/include' ]
     make_command = 'gmake'
 
 # For now, we only support testing the "master" branch.