mesa: make sure the gotten value isn't greater than the

max depth buffer value on 64bit system. fix bug #12095

1 files changed, 5 insertions, 2 deletions

diff --git a/src/mesa/swrast/s_span.c b/src/mesa/swrast/s_span.c
index bbde0025f4..f1e58bd3d8 100644
--- a/src/mesa/swrast/s_span.c
+++ b/src/mesa/swrast/s_span.c
@@ -64,8 +64,11 @@ _swrast_span_default_attribs(GLcontext *ctx, SWspan *span)
       const GLfloat depthMax = ctx->DrawBuffer->_DepthMaxF;
       if (ctx->DrawBuffer->Visual.depthBits <= 16)
          span->z = FloatToFixed(ctx->Current.RasterPos[2] * depthMax + 0.5F);
-      else
-         span->z = (GLint) (ctx->Current.RasterPos[2] * depthMax + 0.5F);
+      else {
+         GLfloat tmpf = ctx->Current.RasterPos[2] * depthMax; 
+         tmpf = MIN2(tmpf, depthMax);
+         span->z = (GLint)tmpf;
+      }
       span->zStep = 0;
       span->interpMask |= SPAN_Z;
    }