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, 28 insertions, 0 deletions

diff --git a/tests/tests2/60_errors_and_warnings.expect b/tests/tests2/60_errors_and_warnings.expect
new file mode 100644
index 0000000..ed6a690
--- /dev/null
+++ b/tests/tests2/60_errors_and_warnings.expect
@@ -0,0 +1,28 @@
+[test_56_btype_excess_1]
+60_errors_and_warnings.c:2: error: too many basic types
+
+[test_57_btype_excess_2]
+60_errors_and_warnings.c:5: error: too many basic types
+
+[test_58_function_redefinition]
+60_errors_and_warnings.c:9: error: redefinition of 'f'
+
+[test_global_redefinition]
+60_errors_and_warnings.c:14: error: redefinition of 'xxx'
+
+[test_59_function_array]
+60_errors_and_warnings.c:17: error: declaration of an array of functions
+
+[test_60_enum_redefinition]
+60_errors_and_warnings.c:21: error: struct/union/enum already defined
+
+[test_62_enumerator_redefinition]
+60_errors_and_warnings.c:26: error: redefinition of enumerator 'RED'
+
+[test_63_local_enumerator_redefinition]
+
+[test_61_undefined_enum]
+60_errors_and_warnings.c:46: error: unknown type size
+
+[test_74_non_const_init]
+60_errors_and_warnings.c:49: error: initializer element is not constant