diff --git a/src/common_audio/signal_processing/cos_table.c b/src/common_audio/signal_processing/cos_table.c
index 7dba4b046..f5b5d52e0 100644
--- a/src/common_audio/signal_processing/cos_table.c
+++ b/src/common_audio/signal_processing/cos_table.c
@@ -16,7 +16,7 @@
 
 #include "signal_processing_library.h"
 
-WebRtc_Word16 WebRtcSpl_kCosTable[] = {
+const WebRtc_Word16 WebRtcSpl_kCosTable[] = {
         8192,  8190,  8187,  8180,  8172,  8160,  8147,  8130,  8112,
         8091,  8067,  8041,  8012,  7982,  7948,  7912,  7874,  7834,
         7791,  7745,  7697,  7647,  7595,  7540,  7483,  7424,  7362,
diff --git a/src/common_audio/signal_processing/hanning_table.c b/src/common_audio/signal_processing/hanning_table.c
index 112d0e592..91a5b5758 100644
--- a/src/common_audio/signal_processing/hanning_table.c
+++ b/src/common_audio/signal_processing/hanning_table.c
@@ -17,7 +17,7 @@
 #include "signal_processing_library.h"
 
 // Hanning table with 256 entries
-WebRtc_Word16 WebRtcSpl_kHanningTable[] = {
+const WebRtc_Word16 WebRtcSpl_kHanningTable[] = {
     1,      2,      6,     10,     15,     22,     30,     39,
    50,     62,     75,     89,    104,    121,    138,    157,
   178,    199,    222,    246,    271,    297,    324,    353,
diff --git a/src/common_audio/signal_processing/include/signal_processing_library.h b/src/common_audio/signal_processing/include/signal_processing_library.h
index 81c55b630..c6574730b 100644
--- a/src/common_audio/signal_processing/include/signal_processing_library.h
+++ b/src/common_audio/signal_processing/include/signal_processing_library.h
@@ -176,13 +176,13 @@ extern "C"
 
 // Trigonometric tables used for quick lookup
 // default declarations
-extern WebRtc_Word16 WebRtcSpl_kCosTable[];
-extern WebRtc_Word16 WebRtcSpl_kSinTable[];
-extern WebRtc_Word16 WebRtcSpl_kSinTable1024[];
+extern const WebRtc_Word16 WebRtcSpl_kCosTable[];
+extern const WebRtc_Word16 WebRtcSpl_kSinTable[];
+extern const WebRtc_Word16 WebRtcSpl_kSinTable1024[];
 // Hanning table
-extern WebRtc_Word16 WebRtcSpl_kHanningTable[];
+extern const WebRtc_Word16 WebRtcSpl_kHanningTable[];
 // Random table
-extern WebRtc_Word16 WebRtcSpl_kRandNTable[];
+extern const WebRtc_Word16 WebRtcSpl_kRandNTable[];
 
 // inline functions:
 #include "spl_inl.h"
diff --git a/src/common_audio/signal_processing/randn_table.c b/src/common_audio/signal_processing/randn_table.c
index 734fa79a6..b4f15409a 100644
--- a/src/common_audio/signal_processing/randn_table.c
+++ b/src/common_audio/signal_processing/randn_table.c
@@ -16,7 +16,7 @@
 
 #include "signal_processing_library.h"
 
-WebRtc_Word16 WebRtcSpl_kRandNTable[] =
+const WebRtc_Word16 WebRtcSpl_kRandNTable[] =
 {
     9178,    -7260,       40,    10189,     4894,    -3531,   -13779,    14764,
    -4008,    -8884,    -8990,     1008,     7368,     5184,     3251,    -5817,
diff --git a/src/common_audio/signal_processing/sin_table.c b/src/common_audio/signal_processing/sin_table.c
index ea44666b4..797bc8ca3 100644
--- a/src/common_audio/signal_processing/sin_table.c
+++ b/src/common_audio/signal_processing/sin_table.c
@@ -16,7 +16,7 @@
 
 #include "signal_processing_library.h"
 
-WebRtc_Word16 WebRtcSpl_kSinTable[] = {
+const WebRtc_Word16 WebRtcSpl_kSinTable[] = {
         0,    142,    285,    428,    571,    713,    856,    998,   1140,
      1281,   1422,   1563,   1703,   1842,   1981,   2120,   2258,   2395,
      2531,   2667,   2801,   2935,   3068,   3200,   3331,   3462,   3591,
diff --git a/src/common_audio/signal_processing/sin_table_1024.c b/src/common_audio/signal_processing/sin_table_1024.c
index a2007f9d8..ff5854ecf 100644
--- a/src/common_audio/signal_processing/sin_table_1024.c
+++ b/src/common_audio/signal_processing/sin_table_1024.c
@@ -16,7 +16,7 @@
 
 #include "signal_processing_library.h"
 
-WebRtc_Word16 WebRtcSpl_kSinTable1024[] =
+const WebRtc_Word16 WebRtcSpl_kSinTable1024[] =
 {
       0,    201,    402,    603,    804,   1005,   1206,   1406,
    1607,   1808,   2009,   2209,   2410,   2610,   2811,   3011,