diff --git a/apps/plugins/2048.c b/apps/plugins/2048.c
index 2f4eb4c001..8c078ef800 100644
--- a/apps/plugins/2048.c
+++ b/apps/plugins/2048.c
@@ -82,9 +82,11 @@ static const unsigned int WINNING_TILE = 2048;
 #  define BEST_SCORE_Y (2*max_numeral_height)
 #endif /* LCD_WIDTH < LCD_HEIGHT */
 
+#if LCD_DEPTH > 1
 /* where to draw the background bitmap */
 static const int BACKGROUND_X = (BASE_X-MIN_SPACE);
 static const int BACKGROUND_Y = (BASE_Y-MIN_SPACE);
+#endif
 
 /* key mappings */
 #define KEY_UP PLA_UP
diff --git a/apps/plugins/lib/xlcd_draw.c b/apps/plugins/lib/xlcd_draw.c
index debdff6f04..98b1004352 100644
--- a/apps/plugins/lib/xlcd_draw.c
+++ b/apps/plugins/lib/xlcd_draw.c
@@ -270,8 +270,8 @@ void xlcd_drawcircle(int cx, int cy, int radius)
 
 
 #if LCD_DEPTH >= 8 && LCD_DEPTH <= 16
-
-#ifdef HAVE_LCD_COLOR
+#if 0 /* unused functions, enable when needed */
+#if defined(HAVE_LCD_COLOR) && (LCD_DEPTH == 16)
 static const fb_data graylut[256] = {
 #if LCD_PIXELFORMAT == RGB565
     0x0000, 0x0000, 0x0000, 0x0020, 0x0020, 0x0821, 0x0821, 0x0841,
@@ -341,10 +341,8 @@ static const fb_data graylut[256] = {
     0xbef7, 0xdef7, 0xdef7, 0xdfff, 0xdfff, 0xffff, 0xffff, 0xffff
 #endif /* LCD_PIXELFORMAT */
 };
-#endif /* HAVE_LCD_COLOR */
+#endif /* HAVE_LCD_COLOR && LCD_DEPTH == 16 */
 
-/* unused functions, enable when needed */
-#if 0
 /* Draw a partial greyscale bitmap, canonical 8 bit format */
 void xlcd_gray_bitmap_part(const unsigned char *src, int src_x, int src_y,
                            int stride, int x, int y, int width, int height)
@@ -412,7 +410,7 @@ void xlcd_gray_bitmap(const unsigned char *src, int x, int y, int width,
 {
     xlcd_gray_bitmap_part(src, 0, 0, width, x, y, width, height);
 }
-#endif
+#endif // unused functions
 
 #ifdef HAVE_LCD_COLOR
 /* Draw a partial colour bitmap, canonical 24 bit RGB format */
diff --git a/apps/plugins/periodic_table.c b/apps/plugins/periodic_table.c
index 23c94e2edd..448f3e1829 100644
--- a/apps/plugins/periodic_table.c
+++ b/apps/plugins/periodic_table.c
@@ -183,6 +183,7 @@ static int font_height = 0;
 
 /* - - - TINYFONT - - - */
 
+#if LCD_DEPTH > 1
 static const long int periodic_tinyfont_bitmaps[] = {
     0x00000000, 0x00220200, 0x00550000, 0x00575750, 0x00236200, 0x00514500, 0x00236300, 0x00220000,
     0x00244200, 0x00211200, 0x00272720, 0x00027200, 0x00000240, 0x00007000, 0x00000200, 0x00122400,
@@ -200,7 +201,6 @@ static const long int periodic_tinyfont_bitmaps[] = {
     0x00052500, 0x00055360, 0x00072700, 0x00162100, 0x00222220, 0x00432400, 0x00630000, 0x00525250
 };
 
-#if LCD_DEPTH > 1
 static void periodic_tinyfont_draw_char(int x, int y, char ch)
 {
     int i,j;
@@ -234,7 +234,7 @@ static void periodic_tinyfont_draw_string(int x, int y, char * s)
         t++;
     }
 }
-#endif
+#endif /* LCD_DEPTH > 1 */
 
 /*
   void periodic_tinyfont_draw_chart(int x, int y, ttk_color col)
diff --git a/apps/root_menu.c b/apps/root_menu.c
index f5cd276484..b39f1acaa6 100644
--- a/apps/root_menu.c
+++ b/apps/root_menu.c
@@ -485,7 +485,7 @@ static const struct root_items items[] = {
     [GO_TO_SHORTCUTMENU] = { do_shortcut_menu, NULL, NULL },
 
 };
-static const int nb_items = sizeof(items)/sizeof(*items);
+//static const int nb_items = sizeof(items)/sizeof(*items);
 
 static int item_callback(int action,
                          const struct menu_item_ex *this_item,
diff --git a/apps/settings_list.c b/apps/settings_list.c
index afd149c06b..b39f8f154f 100644
--- a/apps/settings_list.c
+++ b/apps/settings_list.c
@@ -224,7 +224,9 @@ static const char off_number_spell[] = "off,number,spell";
 static const int timeout_sec_common[] = {-1,0,1,2,3,4,5,6,7,8,9,10,15,20,25,30,
                                         45,60,90,120,180,240,300,600,900,1200,
                                         1500,1800,2700,3600,4500,5400,6300,7200};
+#if defined(HAVE_RECORDING)
 static const int time_recording_trigger[] = {0,1,2,5,10,15,20,25,30,60,120,300,600};
+#endif
 #if defined(HAVE_BACKLIGHT_FADING_INT_SETTING)
 static const int backlight_fade[] = {0,100,200,300,500,1000,2000,3000,5000,10000};
 #endif
@@ -1017,7 +1019,7 @@ const struct settings_list settings[] = {
                   play_frequency, LANG_FREQUENCY, 0, "playback frequency", "auto",
                   UNIT_KHZ, formatter_freq_unit_0_is_auto,
                   getlang_freq_unit_0_is_auto,
-                  playback_frequency_callback, 
+                  playback_frequency_callback,
 #if HAVE_PLAY_FREQ >= 192
                   7,0,SAMPR_44,SAMPR_48,SAMPR_88,SAMPR_96,SAMPR_176,SAMPR_192),
 #elif HAVE_PLAY_FREQ >= 96
@@ -1138,7 +1140,7 @@ const struct settings_list settings[] = {
     INT_SETTING(F_BANFROMQS, max_files_in_playlist,
                 LANG_MAX_FILES_IN_PLAYLIST,
 #if CONFIG_CPU == PP5002 || CONFIG_CPU == PP5020 || CONFIG_CPU == PP5022
-                  /** Slow CPU benefits greatly from building smaller playlists 
+                  /** Slow CPU benefits greatly from building smaller playlists
                   On the iPod Mini 2nd gen, creating a playlist of 2000 entries takes around 10 seconds */
                   2000,
 #elif MEMORYSIZE > 1
@@ -1896,7 +1898,7 @@ const struct settings_list settings[] = {
 #ifdef HAVE_BACKLIGHT
     CHOICE_SETTING(0, backlight_on_button_hold,
                    LANG_BACKLIGHT_ON_BUTTON_HOLD,
-#ifdef HAS_BUTTON_HOLD                   
+#ifdef HAS_BUTTON_HOLD
                    1,
 #else
                    0,
diff --git a/firmware/drivers/usb-designware.c b/firmware/drivers/usb-designware.c
index a5a7a9b099..2933526a1e 100644
--- a/firmware/drivers/usb-designware.c
+++ b/firmware/drivers/usb-designware.c
@@ -158,12 +158,14 @@ static const char* const dw_state_str[EP0_NUM_STATES] =
     [EP0_STATUS_OUT]    = "sts_out",
 };
 
+#if 0
 static const char* const dw_resp_str[3] =
 {
     [USB_CONTROL_ACK]     = "ACK",
     [USB_CONTROL_RECEIVE] = "RECV",
     [USB_CONTROL_STALL]   = "STALL",
 };
+#endif
 
 static struct usb_dw_ep usb_dw_ep_list[USB_NUM_ENDPOINTS][USB_DW_NUM_DIRS];
 static struct usb_dw_ep0 ep0;
diff --git a/lib/rbcodec/codecs/libspeex/sb_celp.c b/lib/rbcodec/codecs/libspeex/sb_celp.c
index 45c8417022..339a7234e5 100644
--- a/lib/rbcodec/codecs/libspeex/sb_celp.c
+++ b/lib/rbcodec/codecs/libspeex/sb_celp.c
@@ -116,11 +116,13 @@ int sb_decoder_ctl(void *state, int request, void *ptr)
 
 #ifdef FIXED_POINT
 static const spx_word16_t gc_quant_bound[16] ICONST_ATTR = {125, 164, 215, 282, 370, 484, 635, 832, 1090, 1428, 1871, 2452, 3213, 4210, 5516, 7228};
+#ifndef SPEEX_DISABLE_ENCODER
 static const spx_word16_t fold_quant_bound[32] ICONST_ATTR = {
    39, 44, 50, 57, 64, 73, 83, 94,
    106, 120, 136, 154, 175, 198, 225, 255,
    288, 327, 370, 420, 476, 539, 611, 692,
    784, 889, 1007, 1141, 1293, 1465, 1660, 1881};
+#endif
 #define LSP_MARGIN 410
 #define LSP_DELTA1 6553
 #define LSP_DELTA2 1638
@@ -188,7 +190,7 @@ static const float h0[64] = {
 extern const spx_word16_t lag_window[];
 extern const spx_word16_t lpc_window[];
 
-#ifndef SPEEX_DISABLE_ENCODER 
+#ifndef SPEEX_DISABLE_ENCODER
 void *sb_encoder_init(const SpeexMode *m)
 {
    int i;
diff --git a/lib/rbcodec/codecs/libspeex/stereo.c b/lib/rbcodec/codecs/libspeex/stereo.c
index e995cde093..55aa6fb1b8 100644
--- a/lib/rbcodec/codecs/libspeex/stereo.c
+++ b/lib/rbcodec/codecs/libspeex/stereo.c
@@ -58,12 +58,14 @@ static const float e_ratio_quant[4] = {.25f, .315f, .397f, .5f};
 static const float e_ratio_quant_bounds[3] = {0.2825f, 0.356f, 0.4485f};
 #else
 static const spx_word16_t e_ratio_quant[4] = {8192, 10332, 13009, 16384};
+#ifndef SPEEX_DISABLE_ENCODER
 static const spx_word16_t e_ratio_quant_bounds[3] = {9257, 11665, 14696};
 static const spx_word16_t balance_bounds[31] = {18, 23, 30, 38, 49, 63,  81, 104,
    134, 172, 221,  284, 364, 468, 600, 771,
    990, 1271, 1632, 2096, 2691, 3455, 4436, 5696,
    7314, 9392, 12059, 15484, 19882, 25529, 32766};
 #endif
+#endif
 
 /* This is an ugly compatibility hack that properly resets the stereo state
    In case it it compiled in fixed-point, but initialised with the deprecated
diff --git a/lib/rbcodec/codecs/libtremor/floor0.c b/lib/rbcodec/codecs/libtremor/floor0.c
index cd0a9f89f6..deec8da92b 100644
--- a/lib/rbcodec/codecs/libtremor/floor0.c
+++ b/lib/rbcodec/codecs/libtremor/floor0.c
@@ -117,6 +117,7 @@ static inline ogg_int32_t toBARK(int n){
   }
 }
 
+#ifndef _V_LSP_MATH_ASM
 static const unsigned char MLOOP_1[64]  ={
    0,10,11,11, 12,12,12,12, 13,13,13,13, 13,13,13,13,
   14,14,14,14, 14,14,14,14, 14,14,14,14, 14,14,14,14,
@@ -132,6 +133,7 @@ static const unsigned char MLOOP_2[64]  ={
 };
 
 static const unsigned char MLOOP_3[8]  ={0,1,2,2,3,3,3,3};
+#endif
 
 static void vorbis_lsp_to_curve(ogg_int32_t *curve,int *map,int n,int ln,
                                 ogg_int32_t *lsp,int m,
diff --git a/lib/rbcodec/metadata/asf.c b/lib/rbcodec/metadata/asf.c
index 04022732aa..39d026237f 100644
--- a/lib/rbcodec/metadata/asf.c
+++ b/lib/rbcodec/metadata/asf.c
@@ -50,6 +50,7 @@ struct asf_object_s {
 };
 typedef struct asf_object_s asf_object_t;
 
+#if 0
 static const guid_t asf_guid_null =
 {0x00000000, 0x0000, 0x0000, {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}};
 
@@ -58,11 +59,12 @@ static const guid_t asf_guid_null =
 static const guid_t asf_guid_header =
 {0x75B22630, 0x668E, 0x11CF, {0xA6, 0xD9, 0x00, 0xAA, 0x00, 0x62, 0xCE, 0x6C}};
 
-static const guid_t asf_guid_data =
-{0x75B22636, 0x668E, 0x11CF, {0xA6, 0xD9, 0x00, 0xAA, 0x00, 0x62, 0xCE, 0x6C}};
-
 static const guid_t asf_guid_index =
 {0x33000890, 0xE5B1, 0x11CF, {0x89, 0xF4, 0x00, 0xA0, 0xC9, 0x03, 0x49, 0xCB}};
+#endif
+
+static const guid_t asf_guid_data =
+{0x75B22636, 0x668E, 0x11CF, {0xA6, 0xD9, 0x00, 0xAA, 0x00, 0x62, 0xCE, 0x6C}};
 
 /* header level object guids */
 
diff --git a/tools/configure b/tools/configure
index 9c7bd8ecd0..7c07b14c90 100755
--- a/tools/configure
+++ b/tools/configure
@@ -4609,7 +4609,7 @@ else
  if test "$gccnum" -ge "601"; then
    # gcc 6 adds a lot of warnings that while useful are too time-consuming
    # to clean up right away
-   GCCOPTS="$GCCOPTS -Wno-shift-negative-value -Wno-unused-const-variable -Wno-nonnull-compare -Wno-tautological-compare"
+   GCCOPTS="$GCCOPTS -Wno-shift-negative-value -Wno-nonnull-compare -Wno-tautological-compare"
  fi
 
  if test "$gccnum" -ge "700"; then