GLK: TADS: Fix GCC Compiler Warnings

These were several undeclared fallthrough warnings i.e. after error
handler cases which will not return and another case of usage of
memset on a non-trivial structure which was fixed by using structure
constructor methods instead.

4 files changed, 13 insertions, 8 deletions

diff --git a/engines/glk/tads/tads2/built_in.h b/engines/glk/tads/tads2/built_in.h
index 5078eda2ee..c735d5627f 100644
--- a/engines/glk/tads/tads2/built_in.h
+++ b/engines/glk/tads/tads2/built_in.h
@@ -52,6 +52,8 @@ struct biffildef {
     osfildef *fp;                          /* underyling system file handle */
     uint      flags;                                               /* flags */
 #define BIFFIL_F_BINARY    0x01                           /* file is binary */
+
+	biffildef() : fp(nullptr), flags(0) {}
 };
 
 /* built-in execution context */
diff --git a/engines/glk/tads/tads2/regex.h b/engines/glk/tads/tads2/regex.h
index 48c2dd0ad4..0f3acfc18b 100644
--- a/engines/glk/tads/tads2/regex.h
+++ b/engines/glk/tads/tads2/regex.h
@@ -46,10 +46,12 @@ typedef int re_state_id;
  *   Group register structure.  Each register keeps track of the starting
  *   and ending offset of the group's text.  
  */
-typedef struct
+typedef struct _re_group_register
 {
     const char *start_ofs;
     const char *end_ofs;
+
+    _re_group_register() : start_ofs(nullptr), end_ofs(nullptr) {}
 } re_group_register;
 
 /* number of group registers we keep */
@@ -98,7 +100,7 @@ typedef struct
  *   state of the compilation and stores the resources associated with the
  *   compiled expression.  
  */
-typedef struct
+typedef struct _re_context
 {
     /* error context */
     errcxdef *errctx;
@@ -135,6 +137,8 @@ typedef struct
 
     /* size of the buffer allocated to strbuf */
     size_t strbufsiz;
+
+    _re_context() : errctx(nullptr), next_state(0), tuple_arr(nullptr), tuples_alloc(0), cur_group(0), strbuf(nullptr), curlen(0), strbufsiz(0) {}
 } re_context;
 
 
diff --git a/engines/glk/tads/tads2/run.cpp b/engines/glk/tads/tads2/run.cpp
index 0def6a771b..03fd80a501 100644
--- a/engines/glk/tads/tads2/run.cpp
+++ b/engines/glk/tads/tads2/run.cpp
@@ -1397,8 +1397,8 @@ resume_from_error:
 					runrepush(ctx, otherbp + runrp2s(p + 4) - 1);
 					p += 6;
 				}
-				break;
 #endif
+				break;
 
 			case OPCGETLCL:
 				runrepush(ctx, ctx->runcxbp + runrp2s(p) - 1);
@@ -1659,19 +1659,19 @@ resume_from_error:
 
 			case OPCEXIT:
 				errsig(ctx->runcxerr, ERR_RUNEXIT);
-				/* NOTREACHED */
+				break;
 
 			case OPCABORT:
 				errsig(ctx->runcxerr, ERR_RUNABRT);
-				/* NOTREACHED */
+				break;
 
 			case OPCASKDO:
 				errsig(ctx->runcxerr, ERR_RUNASKD);
-				/* NOTREACHED */
+				break;
 
 			case OPCASKIO:
 				errsig1(ctx->runcxerr, ERR_RUNASKI, ERRTINT, osrp2(p));
-				/* NOTREACHED */
+				break;
 
 			case OPCJE:
 				p += (runeq(ctx) ? runrp2s(p) : 2);
diff --git a/engines/glk/tads/tads2/runtime_driver.cpp b/engines/glk/tads/tads2/runtime_driver.cpp
index 6f1674d3ac..2eb6602077 100644
--- a/engines/glk/tads/tads2/runtime_driver.cpp
+++ b/engines/glk/tads/tads2/runtime_driver.cpp
@@ -675,7 +675,6 @@ static void trdmain1(errcxdef *ec, int argc, char *argv[],
     dbg.dbgcxlin = (lindef *)0;                      /* no line sources yet */
     
     /* set up built-in function context */
-    CLRSTRUCT(bifctx);
     bifctx.bifcxerr = ec;
     bifctx.bifcxrun = &runctx;
     bifctx.bifcxtio = (tiocxdef *)0;