Please note that the -save-temps option is intended only for use in debugging an application when a developer would like to keep a compilation's intermediate file or representation that would normally be modeled as an internal data structure in the compiler.

The compiler does not guarantee consistent diagnostic detection/reporting while using the -save-temps option.

Original report:

The attachment [^file.c]has these lines ...

    if (test < 10U);
    {
        func1(test);
    }

Note the semi-colon on the first line.  While still legal C, it is probably a user error.

Build it normally, and a warning diagnostic is emitted ...

% tiarmclang -c file.c
file.c:9:20: warning: if statement has empty body [-Wempty-body]
    if (test < 10U);
                   ^
file.c:9:20: note: put the semicolon on a separate line to silence this warning
1 warning generated.

Add the option -save-temps and the diagnostic is not emitted ...

% tiarmclang -c -save-temps file.c
<nothing appears here>