From dab8f25d1c1fae4cbe1f1d4482f21d914b45f1bf Mon Sep 17 00:00:00 2001
From: Andrew Kane <andrew@ankane.org>
Date: Wed, 9 Aug 2023 16:33:54 -0700
Subject: [PATCH] Fixed overflow with vector_norm

---
 src/vector.c                | 6 +++---
 test/expected/functions.out | 6 ++++++
 test/sql/functions.sql      | 1 +
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/src/vector.c b/src/vector.c
index 02964d6..8a2fa54 100644
--- a/src/vector.c
+++ b/src/vector.c
@@ -736,13 +736,13 @@ vector_norm(PG_FUNCTION_ARGS)
 {
 	Vector	   *a = PG_GETARG_VECTOR_P(0);
 	float	   *ax = a->x;
-	float		norm = 0.0;
+	double		norm = 0.0;
 
 	/* Auto-vectorized */
 	for (int i = 0; i < a->dim; i++)
-		norm += ax[i] * ax[i];
+		norm += (double) ax[i] * (double) ax[i];
 
-	PG_RETURN_FLOAT8(sqrt((double) norm));
+	PG_RETURN_FLOAT8(sqrt(norm));
 }
 
 /*
diff --git a/test/expected/functions.out b/test/expected/functions.out
index 6e83da0..16092ba 100644
--- a/test/expected/functions.out
+++ b/test/expected/functions.out
@@ -48,6 +48,12 @@ SELECT vector_norm('[0,1]');
            1
 (1 row)
 
+SELECT vector_norm('[3e37,4e37]')::real;
+ vector_norm 
+-------------
+       5e+37
+(1 row)
+
 SELECT l2_distance('[0,0]', '[3,4]');
  l2_distance 
 -------------
diff --git a/test/sql/functions.sql b/test/sql/functions.sql
index c71291a..78ec8c1 100644
--- a/test/sql/functions.sql
+++ b/test/sql/functions.sql
@@ -11,6 +11,7 @@ SELECT vector_dims('[1,2,3]');
 SELECT round(vector_norm('[1,1]')::numeric, 5);
 SELECT vector_norm('[3,4]');
 SELECT vector_norm('[0,1]');
+SELECT vector_norm('[3e37,4e37]')::real;
 
 SELECT l2_distance('[0,0]', '[3,4]');
 SELECT l2_distance('[0,0]', '[0,1]');