From: Costa Shulyupin <constantine.shulyupin@gmail.com>
Date: Sun, 3 Apr 2022 08:10:41 +0000 (+0300)
Subject: squash warning in SparseMatrix_import_matrix_market/MATRIX_TYPE_COMPLEX
X-Git-Tag: 4.0.0~131^2~1
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=7d0b5e5baba066c0450b91786aaf68390b76d196;p=graphviz

squash warning in SparseMatrix_import_matrix_market/MATRIX_TYPE_COMPLEX

warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result]

On  success,  these functions return the number of input items
successfully matched and assigned; this can be fewer  than
provided  for,  or even zero, in the event of an early
matching failure.
---

diff --git a/cmd/tools/matrix_market.c b/cmd/tools/matrix_market.c
index 83db92fd7..5b74deec1 100644
--- a/cmd/tools/matrix_market.c
+++ b/cmd/tools/matrix_market.c
@@ -213,7 +213,9 @@ SparseMatrix SparseMatrix_import_matrix_market(FILE * f, int format)
 	    val = malloc(2 * nz * sizeof(double));
 	    v = val;
 	    for (i = 0; i < nz; i++) {
-		fscanf(f, "%d %d %lg %lg\n", &I[i], &J[i], &v[0], &v[1]);
+		int num = fscanf(f, "%d %d %lg %lg\n", &I[i], &J[i], &v[0], &v[1]);
+		(void)num;
+		assert(num == 4);
 		v += 2;
 		I[i]--;		/* adjust from 1-based to 0-based */
 		J[i]--;