Cleanup: make surface sample in merge_one_sample() non-static

The merge_one_sample() function adds a sample to the destination
dive if dives are merged. For long periods between samples at surface
depths, it adds a surface interval.

To decrease the number of global objects, make the sample structure
non-static. Of course, initialization of an on-stack structure is
slower. Therefore move it into the corresponding if. Thus, the
structure will be initialized only once per surface-interval.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

1 files changed, 6 insertions, 4 deletions

diff --git a/core/dive.c b/core/dive.c
index 688ccb989..67cfc5fa5 100644
--- a/core/dive.c
+++ b/core/dive.c
@@ -1828,19 +1828,21 @@ static void merge_one_sample(struct sample *sample, int time, struct divecompute
 {
 	int last = dc->samples - 1;
 	if (last >= 0) {
-		static struct sample surface = { .bearing.degrees = -1, .ndl.seconds = -1 };
 		struct sample *prev = dc->sample + last;
 		int last_time = prev->time.seconds;
 		int last_depth = prev->depth.mm;
-		/* Init a few values from prev sample to avoid useless info in XML */
-		surface.bearing.degrees = prev->bearing.degrees;
-		surface.ndl.seconds = prev->ndl.seconds;
 
 		/*
 		 * Only do surface events if the samples are more than
 		 * a minute apart, and shallower than 5m
 		 */
 		if (time > last_time + 60 && last_depth < 5000) {
+			struct sample surface = { 0 };
+
+			/* Init a few values from prev sample to avoid useless info in XML */
+			surface.bearing.degrees = prev->bearing.degrees;
+			surface.ndl.seconds = prev->ndl.seconds;
+
 			add_sample(&surface, last_time + 20, dc);
 			add_sample(&surface, time - 20, dc);
 		}