10 files changed, 30 insertions, 3 deletions
diff --git a/src/backend/optimizer/geqo/geqo_cx.c b/src/backend/optimizer/geqo/geqo_cx.c
index 9f6d5e478aa..c72081e81af 100644
--- a/src/backend/optimizer/geqo/geqo_cx.c
+++ b/src/backend/optimizer/geqo/geqo_cx.c
@@ -38,6 +38,7 @@
 #include "optimizer/geqo_recombination.h"
 #include "optimizer/geqo_random.h"
 
+#if defined(CX)
 
 /* cx
  *
@@ -119,3 +120,5 @@ cx(PlannerInfo *root, Gene *tour1, Gene *tour2, Gene *offspring,
 
 	return num_diffs;
 }
+
+#endif   /* defined(CX) */
diff --git a/src/backend/optimizer/geqo/geqo_erx.c b/src/backend/optimizer/geqo/geqo_erx.c
index 133fe323484..173be444093 100644
--- a/src/backend/optimizer/geqo/geqo_erx.c
+++ b/src/backend/optimizer/geqo/geqo_erx.c
@@ -35,6 +35,7 @@
 #include "optimizer/geqo_recombination.h"
 #include "optimizer/geqo_random.h"
 
+#if defined(ERX)
 
 static int	gimme_edge(PlannerInfo *root, Gene gene1, Gene gene2, Edge *edge_table);
 static void remove_gene(PlannerInfo *root, Gene gene, Edge edge, Edge *edge_table);
@@ -466,3 +467,5 @@ edge_failure(PlannerInfo *root, Gene *gene, int index, Edge *edge_table, int num
 	elog(ERROR, "no edge found");
 	return 0;					/* to keep the compiler quiet */
 }
+
+#endif   /* defined(ERX) */
diff --git a/src/backend/optimizer/geqo/geqo_main.c b/src/backend/optimizer/geqo/geqo_main.c
index 52bd428187b..86213ac5a09 100644
--- a/src/backend/optimizer/geqo/geqo_main.c
+++ b/src/backend/optimizer/geqo/geqo_main.c
@@ -46,14 +46,14 @@ double		Geqo_seed;
 static int	gimme_pool_size(int nr_rel);
 static int	gimme_number_generations(int pool_size);
 
-/* define edge recombination crossover [ERX] per default */
+/* complain if no recombination mechanism is #define'd */
 #if !defined(ERX) && \
 	!defined(PMX) && \
 	!defined(CX)  && \
 	!defined(PX)  && \
 	!defined(OX1) && \
 	!defined(OX2)
-#define ERX
+#error "must choose one GEQO recombination mechanism in geqo.h"
 #endif
 
 
diff --git a/src/backend/optimizer/geqo/geqo_mutation.c b/src/backend/optimizer/geqo/geqo_mutation.c
index 1a06d497757..c6af00a2a76 100644
--- a/src/backend/optimizer/geqo/geqo_mutation.c
+++ b/src/backend/optimizer/geqo/geqo_mutation.c
@@ -35,6 +35,8 @@
 #include "optimizer/geqo_mutation.h"
 #include "optimizer/geqo_random.h"
 
+#if defined(CX)					/* currently used only in CX mode */
+
 void
 geqo_mutation(PlannerInfo *root, Gene *tour, int num_gene)
 {
@@ -60,3 +62,5 @@ geqo_mutation(PlannerInfo *root, Gene *tour, int num_gene)
 		num_swaps -= 1;
 	}
 }
+
+#endif   /* defined(CX) */
diff --git a/src/backend/optimizer/geqo/geqo_ox1.c b/src/backend/optimizer/geqo/geqo_ox1.c
index fbf15282ad8..891cfa2403d 100644
--- a/src/backend/optimizer/geqo/geqo_ox1.c
+++ b/src/backend/optimizer/geqo/geqo_ox1.c
@@ -37,6 +37,7 @@
 #include "optimizer/geqo_random.h"
 #include "optimizer/geqo_recombination.h"
 
+#if defined(OX1)
 
 /* ox1
  *
@@ -90,3 +91,5 @@ ox1(PlannerInfo *root, Gene *tour1, Gene *tour2, Gene *offspring, int num_gene,
 	}
 
 }
+
+#endif   /* defined(OX1) */
diff --git a/src/backend/optimizer/geqo/geqo_ox2.c b/src/backend/optimizer/geqo/geqo_ox2.c
index 01c55bea41c..b43455d3eb6 100644
--- a/src/backend/optimizer/geqo/geqo_ox2.c
+++ b/src/backend/optimizer/geqo/geqo_ox2.c
@@ -37,6 +37,7 @@
 #include "optimizer/geqo_random.h"
 #include "optimizer/geqo_recombination.h"
 
+#if defined(OX2)
 
 /* ox2
  *
@@ -107,3 +108,5 @@ ox2(PlannerInfo *root, Gene *tour1, Gene *tour2, Gene *offspring, int num_gene,
 	}
 
 }
+
+#endif   /* defined(OX2) */
diff --git a/src/backend/optimizer/geqo/geqo_pmx.c b/src/backend/optimizer/geqo/geqo_pmx.c
index deb0f7b353f..e9485cc8b5c 100644
--- a/src/backend/optimizer/geqo/geqo_pmx.c
+++ b/src/backend/optimizer/geqo/geqo_pmx.c
@@ -37,6 +37,7 @@
 #include "optimizer/geqo_random.h"
 #include "optimizer/geqo_recombination.h"
 
+#if defined(PMX)
 
 /* pmx
  *
@@ -219,3 +220,5 @@ pmx(PlannerInfo *root, Gene *tour1, Gene *tour2, Gene *offspring, int num_gene)
 	pfree(indx);
 	pfree(check_list);
 }
+
+#endif   /* defined(PMX) */
diff --git a/src/backend/optimizer/geqo/geqo_px.c b/src/backend/optimizer/geqo/geqo_px.c
index 99289bc11f5..f7f615462c6 100644
--- a/src/backend/optimizer/geqo/geqo_px.c
+++ b/src/backend/optimizer/geqo/geqo_px.c
@@ -37,6 +37,7 @@
 #include "optimizer/geqo_random.h"
 #include "optimizer/geqo_recombination.h"
 
+#if defined(PX)
 
 /* px
  *
@@ -105,3 +106,5 @@ px(PlannerInfo *root, Gene *tour1, Gene *tour2, Gene *offspring, int num_gene,
 	}
 
 }
+
+#endif   /* defined(PX) */
diff --git a/src/backend/optimizer/geqo/geqo_recombination.c b/src/backend/optimizer/geqo/geqo_recombination.c
index ef433e54e58..a61547c16d8 100644
--- a/src/backend/optimizer/geqo/geqo_recombination.c
+++ b/src/backend/optimizer/geqo/geqo_recombination.c
@@ -58,6 +58,9 @@ init_tour(PlannerInfo *root, Gene *tour, int num_gene)
 	}
 }
 
+/* city table is used in these recombination methods: */
+#if defined(CX) || defined(PX) || defined(OX1) || defined(OX2)
+
 /* alloc_city_table
  *
  *	 allocate memory for city table
@@ -85,3 +88,5 @@ free_city_table(PlannerInfo *root, City *city_table)
 {
 	pfree(city_table);
 }
+
+#endif   /* CX || PX || OX1 || OX2 */
diff --git a/src/include/optimizer/geqo.h b/src/include/optimizer/geqo.h
index 6b09c4e1951..be65c054e10 100644
--- a/src/include/optimizer/geqo.h
+++ b/src/include/optimizer/geqo.h
@@ -31,7 +31,7 @@
  #define GEQO_DEBUG
  */
 
-/* recombination mechanism */
+/* choose one recombination mechanism here */
 /*
  #define ERX
  #define PMX