For the curious this flag has been available since GCC 6.1 (2016) and Clang 10 (2020). It is enabled by -Wall for both compilers.

Interestingly (or perhaps coming full circle), the bug reference by the GGP comment is also called out in the GCC 6.1 release notes:

> -Wmisleading-indentation warns about places where the indentation of the code gives a misleading idea of the block structure of the code to a human reader. For example, given CVE-2014-1266

  sslKeyExchange.c: In function 'SSLVerifySignedServerKeyExchange':
    sslKeyExchange.c:629:3: warning: this 'if' clause does not guard... [- 
  Wmisleading-indentation]
    if ((err = SSLHashSHA1.update(&hashCtx, &signedParams)) != 0)
    ^~
  sslKeyExchange.c:631:5: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
        goto fail;
        ^~~~