From 80668031707f8ca41b8e6db25676e9c798d52fb6 Mon Sep 17 00:00:00 2001
From: hoxovic <9694402+hoxovic@users.noreply.github.com>
Date: Fri, 10 Jan 2020 13:25:02 +0100
Subject: [PATCH] Fix emit_go error (#294)

* Add check if:
  - fingerprint suffix is requested, and
  - member is primitive type

If not, don't bother calling lcm_find_struct() when creating array
---
 CMakeLists.txt   |  5 +----
 lcmgen/emit_go.c | 17 ++++++++++++++---
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9922e9c24..6d3a4c26b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -77,10 +77,7 @@ endif()
 lcm_option(
   LCM_ENABLE_GO
   "Build Go utilities, bindings is source distributed"
-
-  # Disable until #294 is resolved
-  FALSE Go)
-  #  GO_FOUND Go)
+  GO_FOUND Go)
 
 option(LCM_ENABLE_TESTS "Build unit tests" ON)
 if(LCM_ENABLE_TESTS)
diff --git a/lcmgen/emit_go.c b/lcmgen/emit_go.c
index 2c5495560..be048428e 100644
--- a/lcmgen/emit_go.c
+++ b/lcmgen/emit_go.c
@@ -278,7 +278,8 @@ uint64_t __lcm_recursive_fingerprint(lcmgen_t *lcm, lcm_struct_t *ls,
             if (ls_ != NULL) {
                 fingerprint += __lcm_recursive_fingerprint(lcm, ls_, &fp);
             } else {
-                fprintf(stderr, "Unable to locate fingerprint for member '%s' of '%s'\n",
+                fprintf(stderr, "Unable to locate fingerprint for member '%s' of '%s'. "
+                                "Are you missing any .lcm files?\n",
                         lm->membername, ls->structname->shortname);
                 return 0;
             }
@@ -567,8 +568,18 @@ static unsigned int emit_go_array_loops(FILE *f, lcmgen_t *lcm, lcm_struct_t *ls
                 map_builtintype_name(lcm_find_member(ls, dim->size)->type->lctypename);
 
             if (slice_emit){
-	        lcm_struct_t *ls_lm = lcm_find_struct(lcm, lm);
-		uint64_t lm_fingerprint = lcm_get_fingerprint(lcm, ls_lm);
+                uint64_t lm_fingerprint = 0;
+                if (!lcm_is_primitive_type(lm->type->lctypename)) {
+                    if (fingerprint != 0) {
+                        lcm_struct_t *ls_lm = lcm_find_struct(lcm, lm);
+                        if (ls_lm == NULL) {
+                            fprintf(stderr, "Unable to locate %s.\n",
+                                    lm->membername);
+                            return -1;
+                        }
+                        lm_fingerprint = lcm_get_fingerprint(lcm, ls_lm);
+                    }
+                }
                 emit_go_slice_make(f, n + 1, ls->structname->package, lm, n, slicestr->str, size,
                                    lm_fingerprint);
 	    }