Fix build warnings.

trunk/src/app/srs_app_rtc_codec.cpp

@@ -49,7 +49,7 @@ public:
     {
         static char buf[4096] = {0};
         int nbytes = vsnprintf(buf, sizeof(buf), fmt, vl);
-        if (nbytes > 0 && nbytes < sizeof(buf)) {
+        if (nbytes > 0 && nbytes < (int)sizeof(buf)) {
             // Srs log is always start with new line, replcae '\n' to '\0', make log easy to read.
             if (buf[nbytes - 1] == '\n') {
                 buf[nbytes - 1] = '\0';

trunk/src/kernel/srs_kernel_error.cpp

@@ -111,7 +111,7 @@ SrsCplxError* SrsCplxError::create(const char* func, const char* file, int line,
     err->line = line;
     err->code = code;
     err->rerrno = rerrno;
-    if (r0 > 0 && r0 < sizeof(buffer)) {
+    if (r0 > 0 && r0 < (int)sizeof(buffer)) {
         err->msg = string(buffer, r0);
     }
     err->wrapped = NULL;
@@ -140,7 +140,7 @@ SrsCplxError* SrsCplxError::wrap(const char* func, const char* file, int line, S
         err->code = v->code;
     }
     err->rerrno = rerrno;
-    if (r0 > 0 && r0 < sizeof(buffer)) {
+    if (r0 > 0 && r0 < (int)sizeof(buffer)) {
         err->msg = string(buffer, r0);
     }
     err->wrapped = v;

trunk/src/kernel/srs_kernel_rtc_rtcp.cpp

@@ -474,8 +474,7 @@ SrsRtcpRR::SrsRtcpRR(uint32_t sender_ssrc)
     header_.version = kRtcpVersion;
     header_.length = 7;
     ssrc_ = sender_ssrc;
-    // TODO: FIXME: Fix warning.
-    memset(&rb_, 0, sizeof(SrsRtcpRB));
+    memset((void*)&rb_, 0, sizeof(SrsRtcpRB));
 }
 
 SrsRtcpRR::~SrsRtcpRR()