Merge pull request #27362 from vrabaud:tsan

asmorkalov · web-flow · commit beeda174833c · 2025-06-06T09:17:07.000+03:00
Fix empty ND-array construction
diff --git a/modules/core/src/matrix.cpp b/modules/core/src/matrix.cpp
@@ -315,7 +315,7 @@ void finalizeHdr(Mat& m)
         m.rows = m.cols = -1;
     if(m.u)
         m.datastart = m.data = m.u->data;
-    if( m.data )
+    if( m.data && d > 0 )
     {
         m.datalimit = m.datastart + m.size[0]*m.step[0];
         if( m.size[0] > 0 )
@@ -328,7 +328,7 @@ void finalizeHdr(Mat& m)
             m.dataend = m.datalimit;
     }
     else
-        m.dataend = m.datalimit = 0;
+        m.dataend = m.datalimit = m.data;
 }
 
 //======================================= Mat ======================================================
diff --git a/modules/core/test/test_mat.cpp b/modules/core/test/test_mat.cpp
@@ -1446,6 +1446,25 @@ TEST(Core_Mat, regression_9507)
     EXPECT_EQ(25u, m2.total());
 }
 
+TEST(Core_Mat, empty)
+{
+    // Should not crash.
+    uint8_t data[2] = {0, 1};
+    cv::Mat mat_nd(/*ndims=*/0, /*sizes=*/nullptr, CV_8UC1, /*data=*/data);
+    cv::Mat1b mat(0, 0, /*data=*/data, /*steps=*/1);
+    EXPECT_EQ(mat_nd.dims, 0);
+    EXPECT_EQ(mat.dims, 2);
+#if CV_VERSION_MAJOR < 5
+    EXPECT_LE(mat_nd.total(), 0u);
+    EXPECT_TRUE(mat_nd.empty());
+#else
+    EXPECT_LE(mat_nd.total(), 1u);
+    EXPECT_FALSE(mat_nd.empty());
+#endif
+    EXPECT_EQ(mat.total(), 0u);
+    EXPECT_TRUE(mat.empty());
+}
+
 TEST(Core_InputArray, empty)
 {
     vector<vector<Point> > data;

Original file line number	Diff line number	Diff line change
`@@ -315,7 +315,7 @@ void finalizeHdr(Mat& m)`
`315`	`315`	`m.rows = m.cols = -1;`
`316`	`316`	`if(m.u)`
`317`	`317`	`m.datastart = m.data = m.u->data;`
`318`		`- if( m.data )`
	`318`	`+ if( m.data && d > 0 )`
`319`	`319`	`{`
`320`	`320`	`m.datalimit = m.datastart + m.size[0]*m.step[0];`
`321`	`321`	`if( m.size[0] > 0 )`
`@@ -328,7 +328,7 @@ void finalizeHdr(Mat& m)`
`328`	`328`	`m.dataend = m.datalimit;`
`329`	`329`	`}`
`330`	`330`	`else`
`331`		`- m.dataend = m.datalimit = 0;`
	`331`	`+ m.dataend = m.datalimit = m.data;`
`332`	`332`	`}`
`333`	`333`
`334`	`334`	`//======================================= Mat ======================================================`