tcc -dt -run ... : simpler is better

* -dt now with lowercase t

* test snippets now separated by real preprocessor statements
  which is valid C also for other compilers

    #if defined test_xxx
       < test snippet x >
    #elif defined test_yyy
       < test snippet y >
    #elif ...
    #endif

* simpler implementation, behaves like -run if no 'test_...' macros
  are seen, works with -E too

* for demonstration I combined some of the small tests for errors
  and warnings (56..63,74) in "60_errors_and_warnings.c"

Also:
* libtcc.c:
  put tcc_preprocess() and tcc_assemble() under the setjmp clause
  to let them return to caller after errors.  This is for -dt -E.
* tccgen.c:
  - get rid of save/restore_parse_state(), macro_ptr is saved
    by begin_macro anyway, now line_num too.
  - use expr_eq for parsing _Generic's controlling_type
  - set nocode_wanted with const_wanted. too, This is to keep
    VT_JMP on vtop when parsing preprocessor expressions.
* tccpp.c: tcc -E: suppress trailing whitespace from lines with
  comments (that -E removes) such as
       NO_GOTPLT_ENTRY,\t    /* never generate ... */

1 files changed, 51 insertions, 0 deletions

diff --git a/tests/tests2/60_errors_and_warnings.c b/tests/tests2/60_errors_and_warnings.c
new file mode 100644
index 0000000..0028caf
--- /dev/null
+++ b/tests/tests2/60_errors_and_warnings.c
@@ -0,0 +1,51 @@
+#if defined test_56_btype_excess_1
+struct A {} int i;
+
+#elif defined test_57_btype_excess_2
+char int i;
+
+#elif defined test_58_function_redefinition
+int f(void) { return 0; }
+int f(void) { return 1; }
+
+#elif defined test_global_redefinition
+int xxx = 1;
+int xxx;
+int xxx = 2;
+
+#elif defined test_59_function_array
+int (*fct)[42](int x);
+
+#elif defined test_60_enum_redefinition
+enum color { RED, GREEN, BLUE };
+enum color { R, G, B };
+enum color c;
+
+#elif defined test_62_enumerator_redefinition
+enum color { RED, GREEN, BLUE };
+enum rgb { RED, G, B};
+enum color c = RED;
+
+#elif defined test_63_local_enumerator_redefinition
+enum {
+    FOO,
+    BAR
+};
+
+int main(void)
+{
+    enum {
+        FOO = 2,
+        BAR
+    };
+
+    return BAR - FOO;
+}
+
+#elif defined test_61_undefined_enum
+enum rgb3 c = 42;
+
+#elif defined test_74_non_const_init
+int i = i++;
+
+#endif