Fix #1298 - shadowing struct mg_str constructor

Makefile

@@ -50,7 +50,6 @@ test++: test
 # Make sure we can build from an unamalgamated sources
 unamalgamated: $(SRCS) $(HDRS) Makefile
 	$(CLANG) src/*.c test/unit_test.c $(CFLAGS) $(LDFLAGS) -g -o unit_test
-
 fuzz: mongoose.c mongoose.h Makefile test/fuzz.c
 	$(CLANG) mongoose.c test/fuzz.c $(CFLAGS) -DMG_ENABLE_LINES -DMG_ENABLE_LOG=0 -fsanitize=fuzzer,signed-integer-overflow,address $(LDFLAGS) -g -o fuzzer
 	$(DEBUGGER) ./fuzzer
@@ -96,7 +95,7 @@ linux: Makefile mongoose.c mongoose.h test/unit_test.c
 	$(GCC) ./unit_test_gcc
 
 linux++: CC = g++
-linux++: WARN += -Wno-shadow  # Ignore "hides constructor for 'struct mg_str'"
+linux++: WARN += -Wno-missing-field-initializers
 linux++: linux
 
 linux-libs: CFLAGS += -fPIC

mongoose.c

@@ -3282,7 +3282,7 @@ void mg_http_serve_ssi(struct mg_connection *c, const char *root,
 
 #include <stdlib.h>
 
-struct mg_str mg_str(const char *s) {
+struct mg_str mg_str_s(const char *s) {
   struct mg_str str = {s, s == NULL ? 0 : strlen(s)};
   return str;
 }

mongoose.h

@@ -459,6 +459,9 @@ struct mg_str {
 #define MG_NULL_STR \
   { NULL, 0 }
 
+// Using macro to avoid shadowing C++ struct constructor, see #1298
+#define mg_str(s) mg_str_s(s)
+
 struct mg_str mg_str(const char *s);
 struct mg_str mg_str_n(const char *s, size_t n);
 int mg_lower(const char *s);

src/str.c

@@ -1,7 +1,7 @@
 #include "str.h"
 #include <stdlib.h>
 
-struct mg_str mg_str(const char *s) {
+struct mg_str mg_str_s(const char *s) {
   struct mg_str str = {s, s == NULL ? 0 : strlen(s)};
   return str;
 }

src/str.h

@@ -11,6 +11,9 @@ struct mg_str {
 #define MG_NULL_STR \
   { NULL, 0 }
 
+// Using macro to avoid shadowing C++ struct constructor, see #1298
+#define mg_str(s) mg_str_s(s)
+
 struct mg_str mg_str(const char *s);
 struct mg_str mg_str_n(const char *s, size_t n);
 int mg_lower(const char *s);