From 8e9c5b3592fdf2b1b016a9da1d1e1f6f1c23ef45 Mon Sep 17 00:00:00 2001
From: "Charlton, Scott R" <charlton@usgs.gov>
Date: Fri, 19 Mar 2021 17:32:10 -0600
Subject: [PATCH] only call qsort with more than one element

---
 phreeqcpp/basicsubs.cpp  |  6 +++---
 phreeqcpp/prep.cpp       |  2 +-
 phreeqcpp/print.cpp      |  2 +-
 phreeqcpp/read.cpp       |  4 ++--
 phreeqcpp/structures.cpp | 10 +++++-----
 phreeqcpp/tidy.cpp       |  8 ++++----
 6 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/phreeqcpp/basicsubs.cpp b/phreeqcpp/basicsubs.cpp
index 208c14bb..d88832ce 100644
--- a/phreeqcpp/basicsubs.cpp
+++ b/phreeqcpp/basicsubs.cpp
@@ -2636,7 +2636,7 @@ edl_species(const char *surf_name, LDBLE * count, char ***names, LDBLE ** moles,
 	/*
 	 *   Sort system species
 	 */
-	if (sys.size() > 0)
+	if (sys.size() > 1)
 	{
 		qsort(&sys[0], sys.size(),
 			  sizeof(struct system_species), system_species_compare);
@@ -2727,12 +2727,12 @@ system_total(const char *total_name, LDBLE * count, char ***names,
 	/*
 	 *   Sort system species
 	 */
-	if (sys.size() > 0 && isort == 0)
+	if (sys.size() > 1 && isort == 0)
 	{
 		qsort(&sys[0], sys.size(),
 			  sizeof(struct system_species), system_species_compare);
 	}
-	else if (sys.size() > 0)
+	else if (sys.size() > 1)
 	{
 		qsort(&sys[0], sys.size(),
 			(size_t)sizeof(struct system_species), system_species_compare_name);
diff --git a/phreeqcpp/prep.cpp b/phreeqcpp/prep.cpp
index b69fb185..77464ce2 100644
--- a/phreeqcpp/prep.cpp
+++ b/phreeqcpp/prep.cpp
@@ -1352,7 +1352,7 @@ build_model(void)
 /*
  *   Sort species list, by master only
  */
-	qsort(&species_list[0], (int)species_list.size(),
+	if (species_list.size() > 1) qsort(&species_list[0], species_list.size(),
 		  sizeof(struct species_list), species_list_compare_master);
 /*
  *   Save model description
diff --git a/phreeqcpp/print.cpp b/phreeqcpp/print.cpp
index 84bcbc47..71c9103c 100644
--- a/phreeqcpp/print.cpp
+++ b/phreeqcpp/print.cpp
@@ -3641,7 +3641,7 @@ print_alkalinity(void)
 				   (double) (total_alkalinity / mass_water_aq_x)));
 		output_msg(sformatf("\t%-15s%12s%12s%10s\n\n", "Species",
 				   "Alkalinity", "Molality", "Alk/Mol"));
-		qsort(&alk_list[0], (size_t) count_alk_list,
+		if (count_alk_list > 1) qsort(&alk_list[0], (size_t) count_alk_list,
 			  (size_t) sizeof(struct species_list), species_list_compare_alk);
 		for (i = 0; i < count_alk_list; i++)
 		{
diff --git a/phreeqcpp/read.cpp b/phreeqcpp/read.cpp
index 05851720..fdd5f9a6 100644
--- a/phreeqcpp/read.cpp
+++ b/phreeqcpp/read.cpp
@@ -1661,14 +1661,14 @@ read_inverse(void)
 /*
  *   Sort isotopes
  */
-	if (inverse[n].count_isotopes > 0)
+	if (inverse[n].count_isotopes > 1)
 	{
 		qsort(inverse[n].isotopes,
 			  (size_t) inverse[n].count_isotopes,
 			  sizeof(struct inv_isotope), inverse_isotope_compare);
 	}
 
-	if (inverse[n].count_i_u > 0)
+	if (inverse[n].count_i_u > 1)
 	{
 		qsort(inverse[n].i_u,
 			  (size_t) inverse[n].count_i_u,
diff --git a/phreeqcpp/structures.cpp b/phreeqcpp/structures.cpp
index 6b006f4b..670500de 100644
--- a/phreeqcpp/structures.cpp
+++ b/phreeqcpp/structures.cpp
@@ -848,7 +848,7 @@ inverse_sort(void)
 /*
  *   Sort array of inverse structures
  */
-	if (count_inverse > 0)
+	if (count_inverse > 1)
 	{
 		qsort(&inverse[0], (size_t) count_inverse,
 			  sizeof(struct inverse), inverse_compare);
@@ -2163,7 +2163,7 @@ save_values_sort(void)
 /*
  *   Sort array of save_values structures
  */
-	if (save_values.size() > 0)
+	if (save_values.size() > 1)
 	{
 		qsort(&save_values[0], save_values.size(),
 			  sizeof(struct save_values), save_values_compare);
@@ -2207,7 +2207,7 @@ save_values_store(struct save_values *s_v)
 		save_values_sort();
 	}
 
-	if (save_values.size() > 0)
+	if (save_values.size() > 1)
 	{
 		qsort(&save_values[0], save_values.size(),
 			sizeof(struct save_values), save_values_compare);
@@ -2409,7 +2409,7 @@ species_list_sort(void)
 /*
  *   Sort list using rules in species_list_compare
  */
-	if (species_list.size() > 0)
+	if (species_list.size() > 1)
 	{
 		qsort(&species_list[0], species_list.size(),
 			  sizeof(struct species_list), species_list_compare);
@@ -2909,7 +2909,7 @@ trxn_sort(void)
 /*
  *   Compare names in tokens in trxn array for sorting
  */
-	if (count_trxn - 1 > 0)
+	if (count_trxn - 1 > 1)
 	{
 		qsort(&trxn.token[1],
 			  (size_t) count_trxn - 1,
diff --git a/phreeqcpp/tidy.cpp b/phreeqcpp/tidy.cpp
index 3d3a140e..cca5d3e2 100644
--- a/phreeqcpp/tidy.cpp
+++ b/phreeqcpp/tidy.cpp
@@ -150,14 +150,14 @@ tidy_model(void)
 /* species */
 	if (new_model == TRUE)
 	{
-		qsort(&s[0], s.size(), sizeof(struct species *), s_compare);
+		if (s.size() > 1) qsort(&s[0], s.size(), sizeof(struct species *), s_compare);
 
 /* master species */
-		qsort(&master[0], master.size(), sizeof(struct master *), master_compare);
+		if (master.size() > 1) qsort(&master[0], master.size(), sizeof(struct master *), master_compare);
 /* elements */
-		qsort(&elements[0], elements.size(), sizeof(struct element *), element_compare);
+		if (elements.size() > 1) qsort(&elements[0], elements.size(), sizeof(struct element *), element_compare);
 /* phases */
-		qsort(&phases[0], phases.size(), sizeof(struct phase *), phase_compare);
+		if (phases.size() > 1) qsort(&phases[0], phases.size(), sizeof(struct phase *), phase_compare);
 
 	}