Fix for old gcc

src/algorithms/telemetry_decoder/gnuradio_blocks/CMakeLists.txt

@@ -74,6 +74,21 @@ if(has_rotl)
     )
 endif()
 
+if(USE_GENERIC_LAMBDAS)
+    set(has_generic_lambdas HAS_GENERIC_LAMBDA=1)
+    set(no_has_generic_lambdas HAS_GENERIC_LAMBDA=0)
+    target_compile_definitions(telemetry_decoder_gr_blocks
+        PRIVATE
+            "$<$<COMPILE_FEATURES:cxx_generic_lambdas>:${has_generic_lambdas}>"
+            "$<$<NOT:$<COMPILE_FEATURES:cxx_generic_lambdas>>:${no_has_generic_lambdas}>"
+    )
+else()
+    target_compile_definitions(telemetry_decoder_gr_blocks
+        PRIVATE
+            -DHAS_GENERIC_LAMBDA=0
+    )
+endif()
+
 if(ENABLE_CLANG_TIDY)
     if(CLANG_TIDY_EXE)
         set_target_properties(telemetry_decoder_gr_blocks

src/algorithms/telemetry_decoder/gnuradio_blocks/gps_l1_ca_telemetry_decoder_gs.cc

@@ -39,8 +39,16 @@ namespace my_rotl = std;
 #else
 namespace my_rotl
 {
-auto rotl = [](auto x, auto n) { return (((x) << (n)) ^ ((x) >> (32 - (n)))); };  // Used in the parity check algorithm
+#ifndef _rotl
-}
+#if HAS_GENERIC_LAMBDA
+auto rotl = [](auto x, auto n) { return (((x) << (n)) ^ ((x) >> (32 - (n)))); };
+#else
+#define rotl(X, N) (((X) << (N)) ^ ((X) >> (32 - (N))))
+#endif
+#else
+#define rotl _rotl
+#endif
+}  // namespace my_rotl
 #endif