Add few compiler warning flags to error

CMakeLists.txt

@@ -2,7 +2,8 @@ cmake_minimum_required(VERSION 3.16)
 project(control_toolbox LANGUAGES CXX)
 
 if(CMAKE_CXX_COMPILER_ID MATCHES "(GNU|Clang)")
-  add_compile_options(-Wall -Wextra -Wpedantic)
+  add_compile_options(-Wall -Wextra -Wpedantic -Werror=conversion -Werror=unused-but-set-variable
+                      -Werror=return-type -Werror=shadow -Werror=format)
 endif()
 
 if(WIN32)

src/limited_proxy.cpp

@@ -144,15 +144,15 @@ double LimitedProxy::update(
 {
   // Get the parameters.  This ensures that they can not change during
   // the calculations and are non-negative!
-  double mass = abs(mass_);          // Estimate of the joint mass
-  double Kd = abs(Kd_);              // Damping gain
-  double Kp = abs(Kp_);              // Position gain
-  double Ki = abs(Ki_);              // Integral gain
-  double Ficl = abs(Ficl_);          // Integral force clamp
-  double Flim = abs(effort_limit_);  // Limit on output force
-  double vlim = abs(vel_limit_);     // Limit on velocity
-  double lam = abs(lambda_proxy_);   // Bandwidth of proxy reconvergence
-  double acon = abs(acc_converge_);  // Acceleration of proxy reconvergence
+  double mass = std::abs(mass_);          // Estimate of the joint mass
+  double Kd = std::abs(Kd_);              // Damping gain
+  double Kp = std::abs(Kp_);              // Position gain
+  double Ki = std::abs(Ki_);              // Integral gain
+  double Ficl = std::abs(Ficl_);          // Integral force clamp
+  double Flim = std::abs(effort_limit_);  // Limit on output force
+  double vlim = std::abs(vel_limit_);     // Limit on velocity
+  double lam = std::abs(lambda_proxy_);   // Bandwidth of proxy reconvergence
+  double acon = std::abs(acc_converge_);  // Acceleration of proxy reconvergence
 
   // For numerical stability, upper bound the bandwidth by 2/dt.
   // Note this is safe for dt==0.

src/pid.cpp

@@ -130,7 +130,7 @@ double Pid::computeCommand(double error, uint64_t dt)
   error_dot_ = d_error_;
 
   // Calculate the derivative error
-  error_dot_ = (error - p_error_last_) / (dt / 1e9);
+  error_dot_ = (error - p_error_last_) / (static_cast<double>(dt) / 1e9);
   p_error_last_ = error;
 
   return computeCommand(error, error_dot_, dt);
@@ -155,7 +155,7 @@ double Pid::computeCommand(double error, double error_dot, uint64_t dt)
   p_term = gains.p_gain_ * p_error_;
 
   // Calculate the integral of the position error
-  i_error_ += (dt / 1e9) * p_error_;
+  i_error_ += (static_cast<double>(dt) / 1e9) * p_error_;
 
   if (gains.antiwindup_ && gains.i_gain_ != 0) {
     // Prevent i_error_ from climbing higher than permitted by i_max_/i_min_