:~> git clone https://github.com/x42/scarlett-mixer
Cloning into 'scarlett-mixer'...
remote: Counting objects: 130, done.
remote: Compressing objects: 100% (36/36), done.
remote: Total 130 (delta 40), reused 75 (delta 34), pack-reused 45
Receiving objects: 100% (130/130), 110.27 KiB | 249.00 KiB/s, done.
Resolving deltas: 100% (59/59), done.
:~> cd  scarlett-mixer/                            
grinder@roadwarrior:~/scarlett-mixer> git submodule init
Submodule 'robtk' (git://github.com/x42/robtk) registered for path 'robtk'
grinder@roadwarrior:~/scarlett-mixer> git submodule update
Cloning into '/home/grinder/scarlett-mixer/robtk'...
Submodule path 'robtk': checked out '05eb4b8398cfd74b30d1d608e169362119c9c7e5'
:~/scarlett-mixer> pkg-config --exists --print-errors cairo pangocairo pango glu gl alsa
:~/scarlett-mixer> make        
cc  \
        -o scarlett-mixer \
        -DVERSION=\"0.1.0-8\" \
        -g -Wall -Wno-unused-function -I. -Irobtk/ `pkg-config --cflags cairo pango lv2 glu alsa` -pthread -DDEFAULT_NOT_ONTOP \
        -DXTERNAL_UI -DHAVE_IDLE_IFACE -DRTK_DESCRIPTOR=lv2ui_descriptor \
        -DPLUGIN_SOURCE=\"src/scarlett_mixer.c\" \
        -DAPPTITLE="\"Scarlett Mixer\"" \
        robtk/robtkapp.c robtk/ui_gl.c robtk/pugl/pugl_x11.c \
         `pkg-config --libs  cairo pangocairo pango glu gl alsa` -lX11 -lm
In file included from robtk/robtk.h:317:0,
                 from robtk/ui_gl.c:101:
robtk/gl/robwidget_gl.h: In function ‘robwidget_child_at’:
robtk/gl/robwidget_gl.h:61:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rw->childcount; ++i) {
  ^
robtk/gl/robwidget_gl.h:61:2: note: use option -std=c99 or -std=gnu99 to compile your code
robtk/gl/robwidget_gl.h: In function ‘decend_into_widget_tree’:
robtk/gl/robwidget_gl.h:77:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rw->childcount; ++i) {
  ^
In file included from robtk/robtk.h:318:0,
                 from robtk/ui_gl.c:101:
robtk/gl/layout.h: In function ‘rcontainer_expose_event_no_clear’:
robtk/gl/layout.h:221:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rw->childcount; ++i) {
  ^
robtk/gl/layout.h: In function ‘rhbox_size_request’:
robtk/gl/layout.h:287:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rw->childcount; ++i) {
  ^
robtk/gl/layout.h:307:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (unsigned int i=0; i < rw->childcount; ++i) {
   ^
robtk/gl/layout.h: In function ‘rhbox_size_allocate’:
robtk/gl/layout.h:346:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (unsigned int i=0; i < rw->childcount; ++i) {
   ^
robtk/gl/layout.h:374:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rw->childcount; ++i) {
  ^
robtk/gl/layout.h:390:20: error: redefinition of ‘i’
  for (unsigned int i=0; i < rw->childcount; ++i) {
                    ^
robtk/gl/layout.h:374:20: note: previous definition of ‘i’ was here
  for (unsigned int i=0; i < rw->childcount; ++i) {
                    ^
robtk/gl/layout.h:390:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rw->childcount; ++i) {
  ^
robtk/gl/layout.h: In function ‘rvbox_size_request’:
robtk/gl/layout.h:468:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rw->childcount; ++i) {
  ^
robtk/gl/layout.h:489:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (unsigned int i=0; i < rw->childcount; ++i) {
   ^
robtk/gl/layout.h: In function ‘rvbox_size_allocate’:
robtk/gl/layout.h:529:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (unsigned int i=0; i < rw->childcount; ++i) {
   ^
robtk/gl/layout.h:558:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rw->childcount; ++i) {
  ^
robtk/gl/layout.h:574:20: error: redefinition of ‘i’
  for (unsigned int i=0; i < rw->childcount; ++i) {
                    ^
robtk/gl/layout.h:558:20: note: previous definition of ‘i’ was here
  for (unsigned int i=0; i < rw->childcount; ++i) {
                    ^
robtk/gl/layout.h:574:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rw->childcount; ++i) {
  ^
In file included from robtk/robtk.h:318:0,
                 from robtk/ui_gl.c:101:
robtk/gl/layout.h: In function ‘rtable_size_request’:
robtk/gl/layout.h:678:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int r=0; r < rt->nrows; ++r) {
  ^
robtk/gl/layout.h:683:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int c=0; c < rt->ncols; ++c) {
  ^
robtk/gl/layout.h:690:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rt->nchilds; ++i) {
  ^
robtk/gl/layout.h:701:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int span_x = tc->left; span_x < tc->right; ++span_x) {
   ^
robtk/gl/layout.h:704:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int span_y = tc->top; span_y < tc->bottom; ++span_y) {
   ^
robtk/gl/layout.h:711:12: error: redefinition of ‘span_x’
   for (int span_x = tc->left; span_x < tc->right; ++span_x) {
            ^
robtk/gl/layout.h:701:12: note: previous definition of ‘span_x’ was here
   for (int span_x = tc->left; span_x < tc->right; ++span_x) {
            ^
robtk/gl/layout.h:711:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int span_x = tc->left; span_x < tc->right; ++span_x) {
   ^
robtk/gl/layout.h:719:12: error: redefinition of ‘span_y’
   for (int span_y = tc->top; span_y < tc->bottom; ++span_y) {
            ^
robtk/gl/layout.h:704:12: note: previous definition of ‘span_y’ was here
   for (int span_y = tc->top; span_y < tc->bottom; ++span_y) {
            ^
robtk/gl/layout.h:719:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int span_y = tc->top; span_y < tc->bottom; ++span_y) {
   ^
robtk/gl/layout.h:734:20: error: redefinition of ‘r’
  for (unsigned int r=0; r < rt->nrows; ++r) {
                    ^
robtk/gl/layout.h:678:20: note: previous definition of ‘r’ was here
  for (unsigned int r=0; r < rt->nrows; ++r) {
                    ^
robtk/gl/layout.h:734:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int r=0; r < rt->nrows; ++r) {
  ^
robtk/gl/layout.h:737:20: error: redefinition of ‘c’
  for (unsigned int c=0; c < rt->ncols; ++c) {
                    ^
robtk/gl/layout.h:683:20: note: previous definition of ‘c’ was here
  for (unsigned int c=0; c < rt->ncols; ++c) {
                    ^
robtk/gl/layout.h:737:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int c=0; c < rt->ncols; ++c) {
  ^
robtk/gl/layout.h: In function ‘rtable_size_allocate’:
robtk/gl/layout.h:790:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (unsigned int r=0; r < rt->nrows; ++r) {
   ^
robtk/gl/layout.h:800:4: error: ‘for’ loop initial declarations are only allowed in C99 mode
    for (unsigned int r=0; r < rt->nrows; ++r) {
    ^
robtk/gl/layout.h:818:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (unsigned int c=0; c < rt->ncols; ++c) {
   ^
robtk/gl/layout.h:829:4: error: ‘for’ loop initial declarations are only allowed in C99 mode
    for (unsigned int c=0; c < rt->ncols; ++c) {
    ^
robtk/gl/layout.h:844:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int c=0; c < rt->ncols; ++c) {
  ^
robtk/gl/layout.h:848:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int r=0; r < rt->nrows; ++r) {
  ^
robtk/gl/layout.h:852:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rt->nchilds; ++i) {
  ^
robtk/gl/layout.h:865:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int span_x = tc->left; span_x < tc->right; ++span_x) {
   ^
robtk/gl/layout.h:868:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int span_y = tc->top; span_y < tc->bottom; ++span_y) {
   ^
robtk/gl/layout.h:883:4: error: ‘for’ loop initial declarations are only allowed in C99 mode
    for (int tci = tc->left; tci < tc->right; ++tci) {
    ^
robtk/gl/layout.h:886:4: error: ‘for’ loop initial declarations are only allowed in C99 mode
    for (int tri = tc->top; tri < tc->bottom; ++tri) {
    ^
robtk/gl/layout.h:912:20: error: redefinition of ‘i’
  for (unsigned int i=0; i < rt->nchilds; ++i) {
                    ^
robtk/gl/layout.h:852:20: note: previous definition of ‘i’ was here
  for (unsigned int i=0; i < rt->nchilds; ++i) {
                    ^
robtk/gl/layout.h:912:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rt->nchilds; ++i) {
  ^
robtk/gl/layout.h:920:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int span_x = tc->left; span_x < tc->right; ++span_x) {
   ^
robtk/gl/layout.h:923:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int span_y = tc->top; span_y < tc->bottom; ++span_y) {
   ^
robtk/gl/layout.h:926:12: error: redefinition of ‘span_x’
   for (int span_x = 0; span_x < tc->left; ++span_x) {
            ^
robtk/gl/layout.h:920:12: note: previous definition of ‘span_x’ was here
   for (int span_x = tc->left; span_x < tc->right; ++span_x) {
            ^
robtk/gl/layout.h:926:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int span_x = 0; span_x < tc->left; ++span_x) {
   ^
robtk/gl/layout.h:929:12: error: redefinition of ‘span_y’
   for (int span_y = 0; span_y < tc->top; ++span_y) {
            ^
robtk/gl/layout.h:923:12: note: previous definition of ‘span_y’ was here
   for (int span_y = tc->top; span_y < tc->bottom; ++span_y) {
            ^
robtk/gl/layout.h:929:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int span_y = 0; span_y < tc->top; ++span_y) {
   ^
robtk/gl/layout.h:980:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (unsigned int i=0; i < rt->nchilds; ++i) {
   ^
robtk/gl/layout.h: In function ‘rtoplevel_cache’:
robtk/gl/layout.h:1066:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rw->childcount; ++i) {
  ^
robtk/gl/layout.h: In function ‘rtoplevel_scale’:
robtk/gl/layout.h:1080:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i=0; i < rw->childcount; ++i) {
  ^
In file included from robtk/robtk.h:326:0,
                 from robtk/ui_gl.c:101:
robtk/widgets/robtk_multibutton.h: In function ‘robtk_mbtn_new’:
robtk/widgets/robtk_multibutton.h:223:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int c = 1; c < modes; ++c) {
  ^
In file included from robtk/robtk.h:327:0,
                 from robtk/ui_gl.c:101:
robtk/widgets/robtk_dial.h: In function ‘robtk_dial_mousemove’:
robtk/widgets/robtk_dial.h:306:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < d->n_detents; ++i) {
  ^
In file included from robtk/robtk.h:330:0,
                 from robtk/ui_gl.c:101:
robtk/widgets/robtk_radiobutton.h: In function ‘btn_group_remove_btn’:
robtk/widgets/robtk_radiobutton.h:52:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i = 0; i < g->cnt; ++i) {
  ^
robtk/widgets/robtk_radiobutton.h: In function ‘btn_group_propagate_change’:
robtk/widgets/robtk_radiobutton.h:81:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i = 0; i < g->cnt; ++i) {
  ^
In file included from robtk/robtk.h:331:0,
                 from robtk/ui_gl.c:101:
robtk/widgets/robtk_scale.h: In function ‘robtk_scale_mousemove’:
robtk/widgets/robtk_scale.h:169:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < d->mark_cnt; ++i) {
  ^
robtk/widgets/robtk_scale.h: In function ‘robtk_scale_render_metrics’:
robtk/widgets/robtk_scale.h:298:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < d->mark_cnt; ++i) {
  ^
In file included from robtk/robtk.h:331:0,
                 from robtk/ui_gl.c:101:
robtk/widgets/robtk_scale.h: In function ‘robtk_scale_destroy’:
robtk/widgets/robtk_scale.h:511:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < d->mark_cnt; ++i) {
  ^
In file included from robtk/robtk.h:334:0,
                 from robtk/ui_gl.c:101:
robtk/widgets/robtk_xyplot.h: In function ‘robtk_xydraw_expose_yraw_line’:
robtk/widgets/robtk_xyplot.h:95:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (uint32_t i = 0; i < d->n_points; ++i) { \
  ^
robtk/widgets/robtk_xyplot.h:214:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(yraw_line,  PR_RAW, DR_LINE)
 ^
robtk/widgets/robtk_xyplot.h:107:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (uint32_t i = d->n_points; i < d->n_points + 1; ++i) { \
   ^
robtk/widgets/robtk_xyplot.h:214:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(yraw_line,  PR_RAW, DR_LINE)
 ^
robtk/widgets/robtk_xyplot.h: In function ‘robtk_xydraw_expose_yraw_zline’:
robtk/widgets/robtk_xyplot.h:95:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (uint32_t i = 0; i < d->n_points; ++i) { \
  ^
robtk/widgets/robtk_xyplot.h:215:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(yraw_zline, PR_RAW, DR_ZLINE)
 ^
robtk/widgets/robtk_xyplot.h:107:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (uint32_t i = d->n_points; i < d->n_points + 1; ++i) { \
   ^
robtk/widgets/robtk_xyplot.h:215:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(yraw_zline, PR_RAW, DR_ZLINE)
 ^
robtk/widgets/robtk_xyplot.h: In function ‘robtk_xydraw_expose_yraw_point’:
robtk/widgets/robtk_xyplot.h:95:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (uint32_t i = 0; i < d->n_points; ++i) { \
  ^
robtk/widgets/robtk_xyplot.h:216:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(yraw_point, PR_RAW, DR_POINT)
 ^
robtk/widgets/robtk_xyplot.h:107:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (uint32_t i = d->n_points; i < d->n_points + 1; ++i) { \
   ^
robtk/widgets/robtk_xyplot.h:216:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(yraw_point, PR_RAW, DR_POINT)
 ^
robtk/widgets/robtk_xyplot.h: In function ‘robtk_xydraw_expose_yavg_line’:
robtk/widgets/robtk_xyplot.h:95:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (uint32_t i = 0; i < d->n_points; ++i) { \
  ^
robtk/widgets/robtk_xyplot.h:218:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(yavg_line,  PR_YAVG, DR_LINE)
 ^
robtk/widgets/robtk_xyplot.h:107:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (uint32_t i = d->n_points; i < d->n_points + 1; ++i) { \
   ^
robtk/widgets/robtk_xyplot.h:218:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(yavg_line,  PR_YAVG, DR_LINE)
 ^
robtk/widgets/robtk_xyplot.h: In function ‘robtk_xydraw_expose_yavg_zline’:
robtk/widgets/robtk_xyplot.h:95:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (uint32_t i = 0; i < d->n_points; ++i) { \
  ^
robtk/widgets/robtk_xyplot.h:219:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(yavg_zline, PR_YAVG, DR_ZLINE)
 ^
robtk/widgets/robtk_xyplot.h:107:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (uint32_t i = d->n_points; i < d->n_points + 1; ++i) { \
   ^
robtk/widgets/robtk_xyplot.h:219:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(yavg_zline, PR_YAVG, DR_ZLINE)
 ^
robtk/widgets/robtk_xyplot.h: In function ‘robtk_xydraw_expose_yavg_point’:
robtk/widgets/robtk_xyplot.h:95:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (uint32_t i = 0; i < d->n_points; ++i) { \
  ^
robtk/widgets/robtk_xyplot.h:220:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(yavg_point, PR_YAVG, DR_POINT)
 ^
robtk/widgets/robtk_xyplot.h:107:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (uint32_t i = d->n_points; i < d->n_points + 1; ++i) { \
   ^
robtk/widgets/robtk_xyplot.h:220:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(yavg_point, PR_YAVG, DR_POINT)
 ^
robtk/widgets/robtk_xyplot.h: In function ‘robtk_xydraw_expose_ymax_line’:
robtk/widgets/robtk_xyplot.h:95:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (uint32_t i = 0; i < d->n_points; ++i) { \
  ^
robtk/widgets/robtk_xyplot.h:222:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(ymax_line,  PR_YMAX, DR_LINE)
 ^
robtk/widgets/robtk_xyplot.h:107:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (uint32_t i = d->n_points; i < d->n_points + 1; ++i) { \
   ^
robtk/widgets/robtk_xyplot.h:222:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(ymax_line,  PR_YMAX, DR_LINE)
 ^
robtk/widgets/robtk_xyplot.h: In function ‘robtk_xydraw_expose_ymax_zline’:
robtk/widgets/robtk_xyplot.h:95:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (uint32_t i = 0; i < d->n_points; ++i) { \
  ^
robtk/widgets/robtk_xyplot.h:223:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(ymax_zline, PR_YMAX, DR_ZLINE)
 ^
robtk/widgets/robtk_xyplot.h:107:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (uint32_t i = d->n_points; i < d->n_points + 1; ++i) { \
   ^
robtk/widgets/robtk_xyplot.h:223:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(ymax_zline, PR_YMAX, DR_ZLINE)
 ^
robtk/widgets/robtk_xyplot.h: In function ‘robtk_xydraw_expose_ymax_point’:
robtk/widgets/robtk_xyplot.h:95:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (uint32_t i = 0; i < d->n_points; ++i) { \
  ^
robtk/widgets/robtk_xyplot.h:224:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(ymax_point, PR_YMAX, DR_POINT)
 ^
robtk/widgets/robtk_xyplot.h:107:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (uint32_t i = d->n_points; i < d->n_points + 1; ++i) { \
   ^
robtk/widgets/robtk_xyplot.h:224:1: note: in expansion of macro ‘GEN_DRAW_FN’
 GEN_DRAW_FN(ymax_point, PR_YMAX, DR_POINT)
 ^
In file included from robtk/robtk.h:335:0,
                 from robtk/ui_gl.c:101:
robtk/widgets/robtk_selector.h: In function ‘robtk_select_size_request’:
robtk/widgets/robtk_selector.h:260:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int i = 0; i < d->item_count; ++i) {
   ^
In file included from robtk/ui_gl.c:300:0:
./src/scarlett_mixer.c: In function ‘open_mixer’:
./src/scarlett_mixer.c:340:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned i = 0; i < NUM_DEVICES; i++) {
  ^
./src/scarlett_mixer.c:396:6: error: conflicting types for ‘i’
  int i = 0;
      ^
./src/scarlett_mixer.c:340:16: note: previous definition of ‘i’ was here
  for (unsigned i = 0; i < NUM_DEVICES; i++) {
                ^
./src/scarlett_mixer.c: In function ‘close_mixer’:
./src/scarlett_mixer.c:420:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i = 0; i < ui->ctrl_cnt; ++i) {
  ^
./src/scarlett_mixer.c: In function ‘set_mute’:
./src/scarlett_mixer.c:433:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int chn = 0; chn <= 2; ++chn) {
  ^
./src/scarlett_mixer.c: In function ‘set_dB’:
./src/scarlett_mixer.c:460:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int chn = 0; chn <= 2; ++chn) {
  ^
./src/scarlett_mixer.c: In function ‘cb_btn_reset’:
./src/scarlett_mixer.c:524:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int r = 0; r < ui->device->sin; ++r) {
  ^
./src/scarlett_mixer.c:531:11: error: redefinition of ‘r’
  for (int r = 0; r < ui->device->smi; ++r) {
           ^
./src/scarlett_mixer.c:524:11: note: previous definition of ‘r’ was here
  for (int r = 0; r < ui->device->sin; ++r) {
           ^
./src/scarlett_mixer.c:531:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int r = 0; r < ui->device->smi; ++r) {
  ^
./src/scarlett_mixer.c:538:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int o = 0; o < ui->device->sout; ++o) {
  ^
./src/scarlett_mixer.c:546:11: error: redefinition of ‘r’
  for (int r = 0; r < ui->device->smi; ++r) {
           ^
./src/scarlett_mixer.c:531:11: note: previous definition of ‘r’ was here
  for (int r = 0; r < ui->device->smi; ++r) {
           ^
./src/scarlett_mixer.c:546:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int r = 0; r < ui->device->smi; ++r) {
  ^
./src/scarlett_mixer.c:547:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (unsigned int c = 0; c < ui->device->smo; ++c) {
   ^
./src/scarlett_mixer.c:559:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int n = 0; n < ui->device->smst; ++n) {
  ^
./src/scarlett_mixer.c: In function ‘cb_set_hiz’:
./src/scarlett_mixer.c:578:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (uint32_t i = 0; i < 2; ++i) {
  ^
./src/scarlett_mixer.c: In function ‘cb_set_pad’:
./src/scarlett_mixer.c:588:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (uint32_t i = 0; i < 4; ++i) {
  ^
./src/scarlett_mixer.c: In function ‘set_select_values’:
./src/scarlett_mixer.c:673:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < mcnt; ++i) {
  ^
./src/scarlett_mixer.c: In function ‘robtk_dial_mouse_intercept’:
./src/scarlett_mixer.c:824:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (uint32_t i = 0; i < ui->device->smo; ++i) {
   ^
./src/scarlett_mixer.c: In function ‘toplevel’:
./src/scarlett_mixer.c:892:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned r = 0; r < ui->device->sin; ++r) {
  ^
./src/scarlett_mixer.c:923:15: error: redeclaration of ‘r’ with no linkage
  unsigned int r;
               ^
./src/scarlett_mixer.c:892:16: note: previous definition of ‘r’ was here
  for (unsigned r = 0; r < ui->device->sin; ++r) {
                ^
./src/scarlett_mixer.c:936:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (unsigned int c = 0; c < ui->device->smo; ++c) {
   ^
./src/scarlett_mixer.c:983:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int c = 0; c < ui->device->smo; ++c) {
  ^
./src/scarlett_mixer.c:1015:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int o = 0; o < ui->device->smst; ++o) {
  ^
./src/scarlett_mixer.c:1043:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i = 0; i < ui->device->num_hiz; ++i) {
  ^
./src/scarlett_mixer.c:1052:20: error: redefinition of ‘i’
  for (unsigned int i = 0; i < ui->device->num_pad; ++i) {
                    ^
./src/scarlett_mixer.c:1043:20: note: previous definition of ‘i’ was here
  for (unsigned int i = 0; i < ui->device->num_hiz; ++i) {
                    ^
./src/scarlett_mixer.c:1052:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i = 0; i < ui->device->num_pad; ++i) {
  ^
./src/scarlett_mixer.c:1061:20: error: redefinition of ‘o’
  for (unsigned int o = 0; o < ui->device->sout; ++o) {
                    ^
./src/scarlett_mixer.c:1015:20: note: previous definition of ‘o’ was here
  for (unsigned int o = 0; o < ui->device->smst; ++o) {
                    ^
./src/scarlett_mixer.c:1061:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int o = 0; o < ui->device->sout; ++o) {
  ^
./src/scarlett_mixer.c: In function ‘gui_cleanup’:
./src/scarlett_mixer.c:1103:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < ui->device->sin; ++i) {
  ^
./src/scarlett_mixer.c:1107:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int r = 0; r < ui->device->smi; ++r) {
  ^
./src/scarlett_mixer.c:1109:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int c = 0; c < ui->device->smo; ++c) {
   ^
./src/scarlett_mixer.c:1113:11: error: redefinition of ‘i’
  for (int i = 0; i < ui->device->smo; ++i) {
           ^
./src/scarlett_mixer.c:1103:11: note: previous definition of ‘i’ was here
  for (int i = 0; i < ui->device->sin; ++i) {
           ^
./src/scarlett_mixer.c:1113:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < ui->device->smo; ++i) {
  ^
./src/scarlett_mixer.c:1116:11: error: redefinition of ‘i’
  for (int i = 0; i < ui->device->sout; ++i) {
           ^
./src/scarlett_mixer.c:1113:11: note: previous definition of ‘i’ was here
  for (int i = 0; i < ui->device->smo; ++i) {
           ^
./src/scarlett_mixer.c:1116:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < ui->device->sout; ++i) {
  ^
./src/scarlett_mixer.c:1119:11: error: redefinition of ‘i’
  for (int i = 0; i < ui->device->smst; ++i) {
           ^
./src/scarlett_mixer.c:1116:11: note: previous definition of ‘i’ was here
  for (int i = 0; i < ui->device->sout; ++i) {
           ^
./src/scarlett_mixer.c:1119:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < ui->device->smst; ++i) {
  ^
./src/scarlett_mixer.c:1124:11: error: redefinition of ‘i’
  for (int i = 0; i < 3; ++i) {
           ^
./src/scarlett_mixer.c:1119:11: note: previous definition of ‘i’ was here
  for (int i = 0; i < ui->device->smst; ++i) {
           ^
./src/scarlett_mixer.c:1124:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < 3; ++i) {
  ^
./src/scarlett_mixer.c:1127:11: error: redefinition of ‘i’
  for (int i = 0; i < 6; ++i) {
           ^
./src/scarlett_mixer.c:1124:11: note: previous definition of ‘i’ was here
  for (int i = 0; i < 3; ++i) {
           ^
./src/scarlett_mixer.c:1127:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < 6; ++i) {
  ^
./src/scarlett_mixer.c:1134:11: error: redefinition of ‘i’
  for (int i = 0; i < ui->device->num_hiz; i++) {
           ^
./src/scarlett_mixer.c:1127:11: note: previous definition of ‘i’ was here
  for (int i = 0; i < 6; ++i) {
           ^
./src/scarlett_mixer.c:1134:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < ui->device->num_hiz; i++) {
  ^
./src/scarlett_mixer.c:1138:11: error: redefinition of ‘i’
  for (int i = 0; i < ui->device->num_pad; i++) {
           ^
./src/scarlett_mixer.c:1134:11: note: previous definition of ‘i’ was here
  for (int i = 0; i < ui->device->num_hiz; i++) {
           ^
./src/scarlett_mixer.c:1138:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; i < ui->device->num_pad; i++) {
  ^
./src/scarlett_mixer.c: In function ‘usage’:
./src/scarlett_mixer.c:1190:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned i = 0; i < NUM_DEVICES; i++) {
  ^
./src/scarlett_mixer.c: In function ‘instantiate’:
./src/scarlett_mixer.c:1234:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; features[i]; ++i) {
  ^
./src/scarlett_mixer.c: In function ‘port_event’:
./src/scarlett_mixer.c:1348:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int r = 0; r < ui->device->sin; ++r) {
  ^
./src/scarlett_mixer.c:1353:20: error: redefinition of ‘r’
  for (unsigned int r = 0; r < ui->device->smi; ++r) {
                    ^
./src/scarlett_mixer.c:1348:20: note: previous definition of ‘r’ was here
  for (unsigned int r = 0; r < ui->device->sin; ++r) {
                    ^
./src/scarlett_mixer.c:1353:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int r = 0; r < ui->device->smi; ++r) {
  ^
./src/scarlett_mixer.c:1357:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (unsigned int c = 0; c < ui->device->smo; ++c) {
   ^
./src/scarlett_mixer.c:1364:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int o = 0; o < ui->device->smst; ++o) {
  ^
./src/scarlett_mixer.c:1374:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int i = 0; i < ui->device->num_hiz; ++i) {
  ^
./src/scarlett_mixer.c:1378:20: error: redefinition of ‘o’
  for (unsigned int o = 0; o < ui->device->sout; ++o) {
                    ^
./src/scarlett_mixer.c:1364:20: note: previous definition of ‘o’ was here
  for (unsigned int o = 0; o < ui->device->smst; ++o) {
                    ^
./src/scarlett_mixer.c:1378:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (unsigned int o = 0; o < ui->device->sout; ++o) {
  ^
robtk/ui_gl.c: In function ‘robtk_expose_ui_scale’:
robtk/ui_gl.c:770:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int y = 0; y < nbtn_row; ++y) {
  ^
robtk/ui_gl.c:771:3: error: ‘for’ loop initial declarations are only allowed in C99 mode
   for (int x = 0; x < nbtn_col; ++x) {
   ^
robtk/ui_gl.c: In function ‘gl_instantiate’:
robtk/ui_gl.c:1454:2: error: ‘for’ loop initial declarations are only allowed in C99 mode
  for (int i = 0; features && features[i]; ++i) {
  ^
Makefile:33: recipe for target 'scarlett-mixer' failed
make: *** [scarlett-mixer] Error 1
:~/scarlett-mixer>