Enabled more warnings, fixed the warnings.
diff --git a/Makefile b/Makefile
index 98bbb06..91e58c5 100644
--- a/Makefile
+++ b/Makefile
@@ -1,14 +1,15 @@
 
 .PHONY: all clean
+CFLAGS=-std=c99 -O3 -Wall -Wextra -pedantic
 all: pbstream.o pbstruct.o tests
 clean:
 	rm -f pbstream.o pbstruct.o tests
 
 pbstream.o: pbstream.c pbstream.h
-	gcc -std=c99 -O3 -Wall -o pbstream.o -c pbstream.c
+	gcc $(CFLAGS) -o pbstream.o -c pbstream.c
 
 pbstruct.o: pbstruct.c pbstruct.h
-	gcc -std=c99 -O3 -Wall -o pbstruct.o -c pbstruct.c
+	gcc $(CFLAGS) -o pbstruct.o -c pbstruct.c
 
 tests: tests.c pbstream.c pbstream.h
-	gcc -std=c99 -O3 -Wall -o tests tests.c
+	gcc $(CFLAGS) -o tests tests.c
diff --git a/pbstream.c b/pbstream.c
index 46a361a..23cff1d 100644
--- a/pbstream.c
+++ b/pbstream.c
@@ -28,9 +28,10 @@
  * To avoid branches, none of these do bounds checking.  So we force clients
  * to overallocate their buffers by >=9 bytes. */
 
-static pbstream_status_t get_v_uint64_t(char **buf, uint64_t *val)
+static pbstream_status_t get_v_uint64_t(uint8_t *restrict *buf,
+                                        uint64_t *restrict val)
 {
-  uint8_t *ptr = (uint8_t*)*buf, b;
+  uint8_t *ptr = *buf, b;
   uint32_t part0 = 0, part1 = 0, part2 = 0;
 
   /* From the original proto2 implementation. */
@@ -47,14 +48,14 @@
   return PBSTREAM_ERROR_UNTERMINATED_VARINT;
 
 done:
-  *buf = (char*)ptr;
+  *buf = ptr;
   *val = (uint64_t)part0 | ((uint64_t)part1 << 28) | ((uint64_t)part2 << 56);
   return PBSTREAM_STATUS_OK;
 }
 
-static pbstream_status_t skip_v_uint64_t(char **buf)
+static pbstream_status_t skip_v_uint64_t(uint8_t **buf)
 {
-  uint8_t *ptr = (uint8_t*)*buf, b;
+  uint8_t *ptr = *buf, b;
   b = *(ptr++); if (!(b & 0x80)) goto done;
   b = *(ptr++); if (!(b & 0x80)) goto done;
   b = *(ptr++); if (!(b & 0x80)) goto done;
@@ -68,13 +69,14 @@
   return PBSTREAM_ERROR_UNTERMINATED_VARINT;
 
 done:
-  *buf = (char*)ptr;
+  *buf = (uint8_t*)ptr;
   return PBSTREAM_STATUS_OK;
 }
 
-static pbstream_status_t get_v_uint32_t(char **buf, uint32_t *val)
+static pbstream_status_t get_v_uint32_t(uint8_t *restrict *buf,
+                                        uint32_t *restrict val)
 {
-  uint8_t *ptr = (uint8_t*)*buf, b;
+  uint8_t *ptr = *buf, b;
   uint32_t result;
 
   /* From the original proto2 implementation. */
@@ -86,29 +88,15 @@
   return PBSTREAM_ERROR_UNTERMINATED_VARINT;
 
 done:
-  *buf = (char*)ptr;
+  *buf = ptr;
   *val = result;
   return PBSTREAM_STATUS_OK;
 }
 
-static pbstream_status_t skip_v_uint32_t(char **buf)
+static pbstream_status_t get_f_uint32_t(uint8_t *restrict *buf,
+                                        uint32_t *restrict val)
 {
-  uint8_t *ptr = (uint8_t*)*buf, b;
-  b = *(ptr++); if (!(b & 0x80)) goto done;
-  b = *(ptr++); if (!(b & 0x80)) goto done;
-  b = *(ptr++); if (!(b & 0x80)) goto done;
-  b = *(ptr++); if (!(b & 0x80)) goto done;
-  b = *(ptr++); if (!(b & 0x80)) goto done;
-  return PBSTREAM_ERROR_UNTERMINATED_VARINT;
-
-done:
-  *buf = (char*)ptr;
-  return PBSTREAM_STATUS_OK;
-}
-
-static pbstream_status_t get_f_uint32_t(char **buf, uint32_t *val)
-{
-  char *b = *buf;
+  uint8_t *b = *buf;
 #define SHL(val, bits) ((uint32_t)val << bits)
   *val = SHL(b[0], 0) | SHL(b[1], 8) | SHL(b[2], 16) | SHL(b[3], 24);
 #undef SHL
@@ -116,15 +104,16 @@
   return PBSTREAM_STATUS_OK;
 }
 
-static pbstream_status_t skip_f_uint32_t(char **buf)
+static pbstream_status_t skip_f_uint32_t(uint8_t **buf)
 {
   *buf += sizeof(uint32_t);
   return PBSTREAM_STATUS_OK;
 }
 
-static pbstream_status_t get_f_uint64_t(char **buf, uint64_t *val)
+static pbstream_status_t get_f_uint64_t(uint8_t *restrict *buf,
+                                        uint64_t *restrict val)
 {
-  char *b = *buf;
+  uint8_t *b = *buf;
   /* TODO: is this worth 32/64 specializing? */
 #define SHL(val, bits) ((uint64_t)val << bits)
   *val = SHL(b[0], 0)  | SHL(b[1], 8)  | SHL(b[2], 16) | SHL(b[3], 24) |
@@ -134,7 +123,7 @@
   return PBSTREAM_STATUS_OK;
 }
 
-static pbstream_status_t skip_f_uint64_t(char **buf)
+static pbstream_status_t skip_f_uint64_t(uint8_t **buf)
 {
   *buf += sizeof(uint64_t);
   return PBSTREAM_STATUS_OK;
@@ -146,23 +135,17 @@
 /* Functions for reading wire values and converting them to values.  These
  * are generated with macros because they follow a higly consistent pattern. */
 
-/* WVTOV() generates a function:
- *   void wvtov_TYPE(wire_t src, val_t *dst, size_t offset)
- * (macro invoker defines the body of the function).  */
 #define WVTOV(type, wire_t, val_t) \
-  static void wvtov_ ## type(wire_t s, val_t *d, size_t offset)
+  static void wvtov_ ## type(wire_t s, val_t *d)
 
-/* GET() generates a function:
- *   pbstream_status_t get_TYPE(char **buf, char *end, size_t offset,
- *                              pbstream_value *dst) */
 #define GET(type, v_or_f, wire_t, val_t, member_name) \
   static pbstream_status_t get_ ## type(struct pbstream_parse_state *s, \
-                                        char *buf, \
+                                        uint8_t *buf, \
                                         struct pbstream_tagged_value *d) { \
     wire_t tmp; \
-    char *b = buf; \
+    uint8_t *b = buf; \
     CHECK(get_ ## v_or_f ## _ ## wire_t(&b, &tmp)); \
-    wvtov_ ## type(tmp, &d->v.member_name, s->offset); \
+    wvtov_ ## type(tmp, &d->v.member_name); \
     s->offset += (b-buf); \
     return PBSTREAM_STATUS_OK; \
   }
@@ -197,10 +180,10 @@
 }
 
 /* Use BYTES version for both STRING and BYTES, leave UTF-8 checks to client. */
-static pbstream_status_t get_BYTES(struct pbstream_parse_state *s, char *buf,
+static pbstream_status_t get_BYTES(struct pbstream_parse_state *s, uint8_t *buf,
                                    struct pbstream_tagged_value *d) {
   uint32_t tmp;
-  char *b = buf;
+  uint8_t *b = buf;
   CHECK(get_v_uint32_t(&b, &tmp));
   s->offset += (b-buf);  /* advance past length varint. */
   wvtov_delimited(tmp, &d->v.delimited, s->offset);
@@ -208,11 +191,11 @@
   return PBSTREAM_STATUS_OK;
 }
 
-static pbstream_status_t get_MESSAGE(struct pbstream_parse_state *s, char *buf,
+static pbstream_status_t get_MESSAGE(struct pbstream_parse_state *s, uint8_t *buf,
                                      struct pbstream_tagged_value *d) {
   /* We're entering a sub-message. */
   uint32_t tmp;
-  char *b = buf;
+  uint8_t *b = buf;
   CHECK(get_v_uint32_t(&b, &tmp));
   s->offset += (b-buf);  /* advance past length varint. */
   wvtov_delimited(tmp, &d->v.delimited, s->offset);
@@ -225,7 +208,7 @@
 
 struct pbstream_type_info {
   pbstream_wire_type_t expected_wire_type;
-  pbstream_status_t (*get)(struct pbstream_parse_state *s, char *buf,
+  pbstream_status_t (*get)(struct pbstream_parse_state *s, uint8_t *buf,
                            struct pbstream_tagged_value *d);
 };
 static struct pbstream_type_info type_info[] = {
@@ -248,7 +231,7 @@
   {PBSTREAM_WIRE_TYPE_DELIMITED, get_MESSAGE}
 };
 
-pbstream_status_t parse_tag(char **buf, struct pbstream_tag *tag)
+pbstream_status_t parse_tag(uint8_t **buf, struct pbstream_tag *tag)
 {
   uint32_t tag_int;
   CHECK(get_v_uint32_t(buf, &tag_int));
@@ -257,7 +240,7 @@
   return PBSTREAM_STATUS_OK;
 }
 
-pbstream_status_t parse_wire_value(char **buf, size_t offset,
+pbstream_status_t parse_wire_value(uint8_t **buf, size_t offset,
                                    pbstream_wire_type_t wt,
                                    union pbstream_wire_value *wv)
 {
@@ -280,7 +263,7 @@
   return PBSTREAM_STATUS_OK;
 }
 
-pbstream_status_t skip_wire_value(char **buf, pbstream_wire_type_t wt)
+pbstream_status_t skip_wire_value(uint8_t **buf, pbstream_wire_type_t wt)
 {
   switch(wt) {
     case PBSTREAM_WIRE_TYPE_VARINT:
@@ -312,7 +295,7 @@
 
 /* Parses and processes the next value from buf. */
 pbstream_status_t pbstream_parse_field(struct pbstream_parse_state *s,
-                                       char *buf,
+                                       uint8_t *buf,
                                        pbstream_field_number_t *fieldnum,
                                        struct pbstream_tagged_value *val,
                                        struct pbstream_tagged_wire_value *wv)
@@ -327,7 +310,7 @@
   }
 
   struct pbstream_tag tag;
-  char *b = buf;
+  uint8_t *b = buf;
   CHECK(parse_tag(&b, &tag));
   s->offset += (b-buf);
   struct pbstream_field *fd = pbstream_find_field(s->top->fieldset,
diff --git a/pbstream.h b/pbstream.h
index 8fcca34..6830689 100644
--- a/pbstream.h
+++ b/pbstream.h
@@ -174,7 +174,7 @@
  * not within 10 bytes of unmapped memory, or the program will segfault. Clients
  * are encouraged to overallocate their buffers by ten bytes to compensate. */
 pbstream_status_t pbstream_parse_field(struct pbstream_parse_state *s,
-                                       char *buf,
+                                       uint8_t *buf,
                                        pbstream_field_number_t *fieldnum,
                                        struct pbstream_tagged_value *val,
                                        struct pbstream_tagged_wire_value *wv);
diff --git a/pbstream_lowlevel.h b/pbstream_lowlevel.h
index 825b554..2fa31a3 100644
--- a/pbstream_lowlevel.h
+++ b/pbstream_lowlevel.h
@@ -24,17 +24,17 @@
 
 /* Parses a single tag from the character data starting at buf, and updates
  * buf to point one past the bytes that were consumed. */
-pbstream_status_t parse_tag(char **buf, struct pbstream_tag *tag);
+pbstream_status_t parse_tag(uint8_t **buf, struct pbstream_tag *tag);
 
 /* Parses a wire value with the given type (which must have been obtained from
  * a tag that was just parsed) and updates buf to point to one past the bytes
  * that were consumed. */
-pbstream_status_t parse_wire_value(char **buf, size_t offset,
+pbstream_status_t parse_wire_value(uint8_t **buf, size_t offset,
                                    pbstream_wire_type_t wt,
                                    union pbstream_wire_value *wv);
 
 /* Like the above, but discards the wire value instead of saving it. */
-pbstream_status_t skip_wire_value(char **buf, pbstream_wire_type_t wt);
+pbstream_status_t skip_wire_value(uint8_t **buf, pbstream_wire_type_t wt);
 
 /* Looks the given field number up in the fieldset, and returns the
  * corresponding pbstream_field definition (or NULL if this field number
diff --git a/tests.c b/tests.c
index 6c9d6fe..79dce46 100644
--- a/tests.c
+++ b/tests.c
@@ -7,37 +7,37 @@
 {
   enum pbstream_status status;
 
-  char zero[] = {0x00};
-  char *zero_buf = zero;
+  uint8_t zero[] = {0x00};
+  uint8_t *zero_buf = zero;
   uint64_t zero_val = 0;
   status = get_v_uint64_t(&zero_buf, &zero_val);
   assert(status == PBSTREAM_STATUS_OK);
   assert(zero_val == 0);
   assert(zero_buf == zero + sizeof(zero));
 
-  char one[] = {0x01};
-  char *one_buf = one;
+  uint8_t one[] = {0x01};
+  uint8_t *one_buf = one;
   uint64_t one_val = 0;
   status = get_v_uint64_t(&one_buf, &one_val);
   assert(status == PBSTREAM_STATUS_OK);
   assert(one_val == 1);
 
-  char twobyte[] = {0xAC, 0x02};
-  char *twobyte_buf = twobyte;
+  uint8_t twobyte[] = {0xAC, 0x02};
+  uint8_t *twobyte_buf = twobyte;
   uint64_t twobyte_val = 0;
   status = get_v_uint64_t(&twobyte_buf, &twobyte_val);
   assert(status == PBSTREAM_STATUS_OK);
   assert(twobyte_val == 300);
 
-  char ninebyte[] = {0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x7F};
-  char *ninebyte_buf = ninebyte;
+  uint8_t ninebyte[] = {0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x7F};
+  uint8_t *ninebyte_buf = ninebyte;
   uint64_t ninebyte_val = 0;
   status = get_v_uint64_t(&ninebyte_buf, &ninebyte_val);
   assert(status == PBSTREAM_STATUS_OK);
-  assert(ninebyte_val == (1LL<<63));
+  assert(ninebyte_val == (1ULL<<63));
 
-  char tenbyte[] = {0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x01};
-  char *tenbyte_buf = tenbyte;
+  uint8_t tenbyte[] = {0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x01};
+  uint8_t *tenbyte_buf = tenbyte;
   uint64_t tenbyte_val = 0;
   status = get_v_uint64_t(&tenbyte_buf, &tenbyte_val);
   assert(status == PBSTREAM_ERROR_UNTERMINATED_VARINT);
@@ -55,7 +55,7 @@
   struct pbstream_fieldset fieldset1;
   pbstream_init_fieldset(&fieldset1, fields1, 2);
 
-  char message1[] = {0x08, 0x96, 0x01};
+  uint8_t message1[] = {0x08, 0x96, 0x01};
   struct pbstream_parse_state s;
   pbstream_init_parser(&s, &fieldset1);
   assert(s.offset == 0);
@@ -68,7 +68,7 @@
   assert(val.v.int32 == 150);
   assert(s.offset == 3);
 
-  char message2[] = {0x12, 0x07, 0x74, 0x65, 0x73, 0x74, 0x69, 0x6e, 0x67};
+  uint8_t message2[] = {0x12, 0x07, 0x74, 0x65, 0x73, 0x74, 0x69, 0x6e, 0x67};
   pbstream_init_parser(&s, &fieldset1);
   assert(pbstream_parse_field(&s, message2, &fieldnum, &val, &wv) ==
          PBSTREAM_STATUS_OK);
@@ -83,7 +83,7 @@
   fields2[0].fieldset = &fieldset1;
   struct pbstream_fieldset fieldset2;
   pbstream_init_fieldset(&fieldset2, fields2, 1);
-  char message3[] = {0x1a, 0x03, 0x08, 0x96, 0x01};
+  uint8_t message3[] = {0x1a, 0x03, 0x08, 0x96, 0x01};
   pbstream_init_parser(&s, &fieldset2);
   assert(pbstream_parse_field(&s, message3, &fieldnum, &val, &wv) ==
          PBSTREAM_STATUS_OK);