Fixing uninitialized vars etc found by building with -O2

src/apflc.c

@@ -139,6 +139,9 @@ main(int argc, const char *argv[])
     (void)argc;
     const char **argp = argv+1;
 
+
+    int rv = 1;
+
     FILE *in = NULL;
     FILE *out = NULL;
 
@@ -159,8 +162,6 @@ main(int argc, const char *argv[])
         goto error_before_ctx;
     }
 
-    int rv = 1;
-
     if (
         (in = openfile(argv[0], name_in, "rb")) == NULL
         || (out = openfile(argv[0], name_out, "wb")) == NULL

src/bytecode.c

@@ -896,9 +896,8 @@ unserialize_ilist(
     struct apfl_string *filename;
     FMT_TRY(unserialize_string(unserializer, &filename));
 
-    size_t tmproots;
+    size_t tmproots = apfl_gc_tmproots_begin(unserializer->gc);
     if (filename != NULL) {
-        tmproots = apfl_gc_tmproots_begin(unserializer->gc);
         if (!apfl_gc_tmproot_add(unserializer->gc, GC_OBJECT_FROM(filename, GC_TYPE_STRING))) {
             return false;
         }

src/context.c

@@ -2433,15 +2433,16 @@ apfl_load(apfl_ctx ctx, struct apfl_source_reader reader, apfl_stackidx name)
     }
 
     struct apfl_error err;
-    if (!apfl_compile_whole_file(
+    bool ok = apfl_compile_whole_file(
         &ctx->gc,
         parser,
         &err,
         ilist
-    )) {
+    );
+    apfl_parser_destroy(parser);
+    apfl_tokenizer_destroy(tokenizer);
+    if (!ok) {
         apfl_drop(ctx, -1);
-        apfl_parser_destroy(parser);
-        apfl_tokenizer_destroy(tokenizer);
         apfl_raise_error_object(ctx, err);
     }
 }

src/re.c

@@ -312,7 +312,7 @@ iter_match(
     size_t i
 ) {
     PCRE2_SIZE *ovector = pcre2_get_ovector_pointer(md);
-    PCRE2_SIZE offset_unadjusted;
+    PCRE2_SIZE offset_unadjusted = 0;
 
     if (i > 0) {
         offset_unadjusted = ovector[1];

src/strings.c

@@ -49,9 +49,11 @@ int
 apfl_string_view_cmp(struct apfl_string_view a, struct apfl_string_view b)
 {
     size_t n = a.len > b.len ? b.len : a.len;
-    int cmp = memcmp(a.bytes, b.bytes, n);
-    if (cmp != 0) {
-        return cmp;
+    if (n != 0) {
+        int cmp = memcmp(a.bytes, b.bytes, n);
+        if (cmp != 0) {
+            return cmp;
+        }
     }
     if (a.len == b.len) {
         return 0;