Enable -Wconversion for core and fix the warnings.

This should help avoid issue 33 in the future.

pb.h

@@ -75,6 +75,7 @@ typedef enum {
     
     /* Number of declared LTYPES */
     PB_LTYPES_COUNT = 7,
+    PB_LTYPE_MASK = 0x0F,
     
     /******************
      * Modifier flags *
@@ -95,11 +96,13 @@ typedef enum {
      * data_offset points to pb_callback_t structure.
      * LTYPE should be 0 (it is ignored, but sometimes
      * used to speculatively index an array). */
-    PB_HTYPE_CALLBACK = 0x30
+    PB_HTYPE_CALLBACK = 0x30,
+    
+    PB_HTYPE_MASK = 0xF0
 } pb_packed pb_type_t;
 
-#define PB_HTYPE(x) ((x) & 0xF0)
-#define PB_LTYPE(x) ((x) & 0x0F)
+#define PB_HTYPE(x) ((x) & PB_HTYPE_MASK)
+#define PB_LTYPE(x) ((x) & PB_LTYPE_MASK)
 
 /* This structure is used in auto-generated constants
  * to specify struct fields.

pb_decode.c

@@ -83,7 +83,7 @@ static bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest)
 bool checkreturn pb_decode_varint(pb_istream_t *stream, uint64_t *dest)
 {
     uint8_t byte;
-    uint8_t bitpos = 0;
+    int bitpos = 0;
     *dest = 0;
     
     while (bitpos < 64 && pb_read(stream, &byte, 1))
@@ -447,7 +447,7 @@ bool checkreturn pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[
         if (PB_HTYPE(iter.current->type) == PB_HTYPE_REQUIRED
             && iter.required_field_index < PB_MAX_REQUIRED_FIELDS)
         {
-            fields_seen[iter.required_field_index >> 3] |= 1 << (iter.required_field_index & 7);
+            fields_seen[iter.required_field_index >> 3] |= (uint8_t)(1 << (iter.required_field_index & 7));
         }
             
         if (!decode_field(stream, wire_type, &iter))
@@ -483,9 +483,9 @@ bool pb_decode_svarint(pb_istream_t *stream, int64_t *dest)
         return false;
     
     if (value & 1)
-        *dest = ~(value >> 1);
+        *dest = (int64_t)(~(value >> 1));
     else
-        *dest = value >> 1;
+        *dest = (int64_t)(value >> 1);
     
     return true;
 }

pb_encode.c

@@ -205,7 +205,7 @@ bool checkreturn pb_encode(pb_ostream_t *stream, const pb_field_t fields[], cons
 bool checkreturn pb_encode_varint(pb_ostream_t *stream, uint64_t value)
 {
     uint8_t buffer[10];
-    int i = 0;
+    size_t i = 0;
     
     if (value == 0)
         return pb_write(stream, (uint8_t*)&value, 1);
@@ -225,9 +225,9 @@ bool checkreturn pb_encode_svarint(pb_ostream_t *stream, int64_t value)
 {
     uint64_t zigzagged;
     if (value < 0)
-        zigzagged = ~(value << 1);
+        zigzagged = (uint64_t)(~(value << 1));
     else
-        zigzagged = value << 1;
+        zigzagged = (uint64_t)(value << 1);
     
     return pb_encode_varint(stream, zigzagged);
 }
@@ -266,7 +266,7 @@ bool checkreturn pb_encode_fixed64(pb_ostream_t *stream, const void *value)
     #endif
 }
 
-bool checkreturn pb_encode_tag(pb_ostream_t *stream, pb_wire_type_t wiretype, int field_number)
+bool checkreturn pb_encode_tag(pb_ostream_t *stream, pb_wire_type_t wiretype, uint32_t field_number)
 {
     uint64_t tag = wiretype | (field_number << 3);
     return pb_encode_varint(stream, tag);
@@ -370,7 +370,7 @@ bool checkreturn pb_enc_varint(pb_ostream_t *stream, const pb_field_t *field, co
 
 bool checkreturn pb_enc_svarint(pb_ostream_t *stream, const pb_field_t *field, const void *src)
 {
-    uint64_t value = 0;
+    int64_t value = 0;
     
     switch (field->data_size)
     {

pb_encode.h

@@ -54,7 +54,7 @@ bool pb_encode_tag_for_field(pb_ostream_t *stream, const pb_field_t *field);
 
 /* Encode field header by manually specifing wire type. You need to use this if
  * you want to write out packed arrays from a callback field. */
-bool pb_encode_tag(pb_ostream_t *stream, pb_wire_type_t wiretype, int field_number);
+bool pb_encode_tag(pb_ostream_t *stream, pb_wire_type_t wiretype, uint32_t field_number);
 
 /* Encode an integer in the varint format.
  * This works for bool, enum, int32, int64, uint32 and uint64 field types. */

tests/Makefile

@@ -4,7 +4,7 @@ DEPS=../pb_decode.h ../pb_encode.h ../pb.h person.pb.h callbacks.pb.h unittests.
 TESTS=test_decode1 test_encode1 decode_unittests encode_unittests test_no_messages
 
 # More strict checks for the core part of nanopb
-CFLAGS_CORE=-pedantic -Wextra -Wcast-qual -Wlogical-op
+CFLAGS_CORE=-pedantic -Wextra -Wcast-qual -Wlogical-op -Wconversion
 
 all: breakpoints $(TESTS) run_unittests