Fix dump-c output involving typedef names

Follow-up to 99067de, which made expr2c prefer typedef names over
original type expressions.

Thanks Andreas Stahlbauer for providing the regression tests and help in
debugging.

Fixes: diffblue#882
Fixes: diffblue#964
Fixes: diffblue#972

Author: tautschnig

regression/goto-instrument/typedef1/main.c

@@ -0,0 +1,69 @@
+typedef long int off_t;
+typedef signed char smallint;
+
+typedef struct chain_s {
+  struct node_s *first;
+  struct node_s *last;
+  const char *programname;
+} chain;
+
+typedef struct func_s {
+    struct chain_s body;
+} func;
+
+typedef struct node_s {
+  struct node_s *n;
+} node;
+
+typedef struct dumper_t_x {
+  node n;
+  off_t dump_skip;
+  signed int dump_length;
+  smallint dump_vflag;
+} dumper_t;
+
+typedef struct FS_x {
+  struct FS *nextfs;
+  signed int bcnt;
+} FS;
+
+dumper_t * alloc_dumper(void) {
+  return (void*) 0;
+}
+
+typedef unsigned int uint32_t;
+
+const uint32_t xx[2];
+
+typedef struct node_s2 {
+  uint32_t info;
+} node2;
+
+typedef struct {
+  int x;
+} anon_name;
+
+typedef struct node_s3 {
+  union {
+    struct node_s *n;
+    func *f;
+  } r;
+} node3;
+
+typedef int x_int;
+typedef int y_int;
+typedef x_int *p_int;
+
+int main() {
+  node n;
+  chain c;
+  dumper_t a;
+  dumper_t b[3];
+  node2* sn;
+  anon_name d;
+  node3* s3;
+  y_int y;
+  p_int p;
+  alloc_dumper();
+  return 0;
+}

regression/goto-instrument/typedef1/test.desc

@@ -0,0 +1,10 @@
+CORE
+main.c
+--dump-c
+^EXIT=0$
+^SIGNAL=0$
+--
+^warning: ignoring
+--
+This test should be run via chain.sh, which will try to recompile the dumped C
+code. Missing/incomplete typedef output would cause a failure.

regression/goto-instrument/typedef2/main.c

@@ -0,0 +1,16 @@
+typedef struct
+{
+	char bogus;
+} bb_mbstate_t;
+
+int bb_wcrtomb(char *s, char wc, bb_mbstate_t *ps);
+
+int bb_wcrtomb(char *s, char wc, bb_mbstate_t *ps)
+{
+	return 1;
+}
+
+int main() {
+	bb_wcrtomb("foo", 'Z', (void*)1);
+	return 0;
+}

regression/goto-instrument/typedef2/test.desc

@@ -0,0 +1,10 @@
+CORE
+main.c
+--dump-c
+^EXIT=0$
+^SIGNAL=0$
+--
+^warning: ignoring
+--
+This test should be run via chain.sh, which will try to recompile the dumped C
+code. Missing/incomplete typedef output would cause a failure.

regression/goto-instrument/typedef3/main.c

@@ -0,0 +1,30 @@
+extern void* memset(void *, int, unsigned long);
+
+typedef void (*__sighandler_t) (int);
+
+typedef __sighandler_t sighandler_t;
+
+typedef struct siginfo {
+  int si_signo;
+} siginfo_t;
+
+struct sigaction {
+  union {
+    __sighandler_t _sa_handler;
+    void (*_sa_sigaction)(int, struct siginfo *, void *);
+  } _u;
+};
+
+#define sa_sigaction  _u._sa_sigaction
+#define sa_handler  _u._sa_handler
+
+static void askpass_timeout(signed int ignore) {
+  ;
+}
+
+int main() {
+  struct sigaction sa, oldsa;
+  memset(&sa, 0, sizeof(sa));
+  sa.sa_handler = askpass_timeout;
+  return 0;
+}

regression/goto-instrument/typedef3/test.desc

@@ -0,0 +1,10 @@
+CORE
+main.c
+--dump-c
+^EXIT=0$
+^SIGNAL=0$
+--
+^warning: ignoring
+--
+This test should be run via chain.sh, which will try to recompile the dumped C
+code. Missing/incomplete typedef output would cause a failure.