diff --git a/app/gegl/gimpoperationcagecoefcalc.c b/app/gegl/gimpoperationcagecoefcalc.c
index e1700b03bd..30e8c9e8d0 100644
--- a/app/gegl/gimpoperationcagecoefcalc.c
+++ b/app/gegl/gimpoperationcagecoefcalc.c
@@ -255,7 +255,7 @@ gimp_operation_cage_coef_calc_process (GeglOperation       *operation,
                   L10 = L1 - L0;
 
                   /* edge coef */
-                  coef[j + n_cage_vertices] = (-absa / (4.0 * M_PI)) * ((4.0*S-(R*R)/Q) * A10 + (R / (2.0 * Q)) * L10 + L1 - 2.0);
+                  coef[j + n_cage_vertices] = (-absa / (4.0 * G_PI)) * ((4.0*S-(R*R)/Q) * A10 + (R / (2.0 * Q)) * L10 + L1 - 2.0);
 
                   if (isnan(coef[j + n_cage_vertices]))
                     {
@@ -265,8 +265,8 @@ gimp_operation_cage_coef_calc_process (GeglOperation       *operation,
                   /* vertice coef */
                   if (!gimp_operation_cage_coef_calc_is_on_straight (&v1, &v2, &p))
                     {
-                      coef[j] += (BA / (2.0 * M_PI)) * (L10 /(2.0*Q) - A10 * (2.0 + R / Q));
-                      coef[(j+1)%n_cage_vertices] -= (BA / (2.0 * M_PI)) * (L10 / (2.0 * Q) - A10 * (R / Q));
+                      coef[j] += (BA / (2.0 * G_PI)) * (L10 /(2.0*Q) - A10 * (2.0 + R / Q));
+                      coef[(j+1)%n_cage_vertices] -= (BA / (2.0 * G_PI)) * (L10 / (2.0 * Q) - A10 * (R / Q));
                     }
 
                   last = current;
diff --git a/plug-ins/imagemap/imap_main.c b/plug-ins/imagemap/imap_main.c
index 65514bf27c..d944ab418c 100644
--- a/plug-ins/imagemap/imap_main.c
+++ b/plug-ins/imagemap/imap_main.c
@@ -326,7 +326,7 @@ draw_rectangle(cairo_t *cr, gboolean filled, gint x, gint y,
 void
 draw_circle(cairo_t *cr, gint x, gint y, gint r)
 {
-   cairo_arc (cr, ZOOMED (x), ZOOMED (y), ZOOMED (r), 0., 2 * M_PI);
+   cairo_arc (cr, ZOOMED (x), ZOOMED (y), ZOOMED (r), 0., 2 * G_PI);
    cairo_stroke (cr);
 }
 
diff --git a/plug-ins/lighting/lighting-preview.c b/plug-ins/lighting/lighting-preview.c
index f3c5dc38bb..e1319de573 100644
--- a/plug-ins/lighting/lighting-preview.c
+++ b/plug-ins/lighting/lighting-preview.c
@@ -315,12 +315,12 @@ draw_handles (void)
         case POINT_LIGHT:
         case SPOT_LIGHT:
           cairo_arc (cr, handle_xpos, handle_ypos,
-                     LIGHT_SYMBOL_SIZE/2, 0, 2 * M_PI);
+                     LIGHT_SYMBOL_SIZE/2, 0, 2 * G_PI);
           cairo_fill (cr);
           break;
         case DIRECTIONAL_LIGHT:
           cairo_arc (cr, handle_xpos, handle_ypos,
-                     LIGHT_SYMBOL_SIZE/2, 0, 2 * M_PI);
+                     LIGHT_SYMBOL_SIZE/2, 0, 2 * G_PI);
           cairo_fill (cr);
           cairo_move_to (cr, handle_xpos, handle_ypos);
           cairo_line_to (cr, startx + pw/2, starty + ph/2);
diff --git a/plug-ins/map-object/map-object-preview.c b/plug-ins/map-object/map-object-preview.c
index c270745ac7..d9a20b18d8 100644
--- a/plug-ins/map-object/map-object-preview.c
+++ b/plug-ins/map-object/map-object-preview.c
@@ -225,7 +225,7 @@ draw_light_marker (cairo_t *cr,
   lightx = xpos;
   lighty = ypos;
 
-  cairo_arc (cr, lightx, lighty, 7, 0, 2 * M_PI);
+  cairo_arc (cr, lightx, lighty, 7, 0, 2 * G_PI);
   cairo_fill (cr);
 }