Created attachment 153754 [details]
This lets the C compiler show warnings

When valac generates C code for the attachted source files, everything is fine and no warnings are displayed:

$ valac -C upval.vala

As soon as the generated C source code is compiled by gcc-4.3, however, the following warnings are displayed by the C compiler:

$ LC_ALL=C gcc -o upval `pkg-config --cflags --libs vala-1.0` upval.c
upval.c: In function 'gen':
upval.c:91: warning: assignment from incompatible pointer type
upval.c:92: warning: assignment from incompatible pointer type
upval.c:93: warning: assignment from incompatible pointer type

The contents of the 3 lines mentioned above is as follows:

        *v2set = (_tmp0_ = __lambda0__noargs_func, (((*v2set_target_destroy_notify) == NULL) ? NULL : (*v2set_target_destroy_notify) (*v2set_target), *v2set = NULL, *v2set_target = NULL, *v2set_target_destroy_notify = NULL), *v2set_target = block1_data_ref (_data1_), *v2set_target_destroy_notify = block1_data_unref, _tmp0_);
        *v3set = (_tmp1_ = __lambda1__noargs_func, (((*v3set_target_destroy_notify) == NULL) ? NULL : (*v3set_target_destroy_notify) (*v3set_target), *v3set = NULL, *v3set_target = NULL, *v3set_target_destroy_notify = NULL), *v3set_target = block1_data_ref (_data1_), *v3set_target_destroy_notify = block1_data_unref, _tmp1_);
        result = (_tmp2_ = __lambda2__noargs_func, *result_target = block1_data_ref (_data1_), *result_target_destroy_notify = block1_data_unref, _tmp2_);

I have been using valac 0.7.10.