Description

Passing an invalid DSN during sentry_options_set_dsn() causes crash

When does the problem happen

• During build
• [x ] During run-time
• When capturing a hard crash

Environment

• OS: Windows 10, 64-bit
• Compiler: MSVC 19

Steps To Reproduce
Pass a dsn starting wiht "=" to sentry, e.g.
"=https://[email protected]/1234567"

Log output
Sentry crashes during url cleanup with call stack:

 	ucrtbase.dll!00007fffca63f05b()	Unknown
 	UE4Editor-SentryClient-Win64-DebugGame.dll!sentry__url_cleanup(sentry_url_t * url) Line 206	C
>	UE4Editor-SentryClient-Win64-DebugGame.dll!sentry__dsn_new(const char * raw_dsn) Line 273	C
 	UE4Editor-SentryClient-Win64-DebugGame.dll!sentry_options_set_dsn(sentry_options_s * opts, const char * raw_dsn) Line 120	C

It is trying to free a nullptr (url->host) here:

void
sentry__url_cleanup(sentry_url_t *url)
{
    sentry_free(url->scheme);
    sentry_free(url->host);
    sentry_free(url->path);
    sentry_free(url->query);
    sentry_free(url->fragment);
    sentry_free(url->username);
    sentry_free(url->password);

All the url components, except scheme, are NULL