Fix Warnings in Release Build

[nosracd]

This PR:

• Adds two addition CI jobs which run the Ubuntu builds with release flags (ea8a740)
• Initializes variables with a nominal value (d9327cf)
• Refactors size variables to an unsigned integer (b96cb3c)
• Decreases the size of C strings so they can be appended to without warnings occurring (745cdd2)

Resolves #457.

This PR does not fix GCC 12 release build warnings (it is possible to use the Fedora target to produce those).

[ihilt]

I think since we are setting the length of the destination buffer, we could use snprintf instead of reducing its length like this. snprintf is safer than sprintf in this case since it terminates the output with '\0', avoids the original error message, and allows us to check for truncation. (Although it does still check the length of the source buffer.) If truncation of the output occurs, snprintf would return PATH_MAX or greater in this case and if an error occurs it returns a negative value. I would assume in either of these cases we wouldn't be able to rely on the buffer to hold a valid path so logging an error and returning a negative value seems appropriates since under similar circumstances the same thing is done a little further down. If you agree with this approach, the same thing could be done in emit_python.c.

diff --git a/lcmgen/emit_lua.c b/lcmgen/emit_lua.c
index 080bc55..481a890 100644
--- a/lcmgen/emit_lua.c
+++ b/lcmgen/emit_lua.c
@@ -751,10 +751,20 @@ static int emit_package(lcmgen_t *lcm, _package_contents_t *pc)
     int have_package = dirs[0] != NULL;
     int write_init_lua = !getopt_get_bool(lcm->gopt, "lua-no-init");
 
-    sprintf(package_dir_prefix, "%s%s", getopt_get_string(lcm->gopt, "lpath"),
+    int ret = snprintf(package_dir_prefix, PATH_MAX, "%s%s", getopt_get_string(lcm->gopt, "lpath"),
             strlen(getopt_get_string(lcm->gopt, "lpath")) > 0 ? G_DIR_SEPARATOR_S : "");
-    sprintf(package_dir, "%s%s%s", package_dir_prefix, pdname,
+    if (ret >= PATH_MAX || ret < 0) {
+	    free(pdname);
+	    err("Could not create package directory prefix string\n");
+	    return -1;
+    }
+    ret = snprintf(package_dir, PATH_MAX, "%s%s%s", package_dir_prefix, pdname,
             have_package ? G_DIR_SEPARATOR_S : "");
+    if (ret >= PATH_MAX || ret < 0) {
+	    free(pdname);
+	    err("Could not create package directory string\n");
+	    return -1;
+    }
     free(pdname);
     if (strlen(package_dir)) {
         if (!g_file_test(package_dir, G_FILE_TEST_EXISTS)) {

[nosracd]

Like so? 68782e4