diff --git a/src/mono/mono/mini/aot-compiler.c b/src/mono/mono/mini/aot-compiler.c
index 1aab82ecc5271..02fe5463309e9 100644
--- a/src/mono/mono/mini/aot-compiler.c
+++ b/src/mono/mono/mini/aot-compiler.c
@@ -4212,22 +4212,23 @@ get_plt_entry (MonoAotCompile *acfg, MonoJumpInfo *patch_info)
 			res->debug_sym = get_plt_entry_debug_sym (acfg, res->ji, acfg->plt_entry_debug_sym_cache);
 		if (synchronized) {
 			/* Avoid duplicate symbols because we don't cache */
+			char *tmp_symbol = res->symbol;
 			res->symbol = g_strdup_printf ("%s_%d", res->symbol, synchronized_symbol_idx);
-			if (res->debug_sym)
+			g_free (tmp_symbol);
+			if (res->debug_sym) {
+				char *tmp_debug_sym = res->debug_sym;
 				res->debug_sym = g_strdup_printf ("%s_%d", res->debug_sym, synchronized_symbol_idx);
+				g_free (tmp_debug_sym);
+			}
 			synchronized_symbol_idx ++;
 		}
 
 		if (res->debug_sym)
-			res->llvm_symbol = g_strdup_printf ("%s_%s_llvm", res->symbol, res->debug_sym);
+			res->llvm_symbol = mono_mempool_strdup_printf (acfg->mempool, "%s_%s_llvm", res->symbol, res->debug_sym);
 		else
-			res->llvm_symbol = g_strdup_printf ("%s_llvm", res->symbol);
-		if (strstr (res->llvm_symbol, acfg->temp_prefix) == res->llvm_symbol) {
-			/* The llvm symbol shouldn't be temporary, since the llvm generated object file references it */
-			char *tmp = res->llvm_symbol;
-			res->llvm_symbol = g_strdup (res->llvm_symbol + strlen (acfg->temp_prefix));
-			g_free (tmp);
-		}
+			res->llvm_symbol = mono_mempool_strdup_printf (acfg->mempool, "%s_llvm", res->symbol);
+		if (strstr (res->llvm_symbol, acfg->temp_prefix) == res->llvm_symbol)
+			res->llvm_symbol = res->llvm_symbol + strlen (acfg->temp_prefix);
 
 		g_hash_table_insert (acfg->patch_to_plt_entry [new_ji->type], new_ji, res);
 
@@ -7003,7 +7004,7 @@ emit_and_reloc_code (MonoAotCompile *acfg, MonoMethod *method, guint8 *code, gui
 /*
  * sanitize_symbol:
  *
- *   Return a modified version of S which only includes characters permissible in symbols.
+ *   Returns either S or a malloc-ed modified version of S which only includes characters permissible in symbols.
  */
 static char*
 sanitize_symbol (MonoAotCompile *acfg, char *s)
@@ -7045,7 +7046,7 @@ sanitize_symbol (MonoAotCompile *acfg, char *s)
 		}
 	}
 
-	res = mono_mempool_strdup (acfg->mempool, gs->str);
+	res = g_strdup (gs->str);
 	g_string_free (gs, TRUE);
 	return res;
 }
@@ -8039,7 +8040,12 @@ get_plt_entry_debug_sym (MonoAotCompile *acfg, MonoJumpInfo *ji, GHashTable *cac
 
 	g_free (prefix);
 
-	return sanitize_symbol (acfg, debug_sym);
+	char *tmp_debug_sym = debug_sym;
+	debug_sym = sanitize_symbol (acfg, debug_sym);
+	if (tmp_debug_sym != debug_sym)
+		g_free (tmp_debug_sym);
+
+	return debug_sym;
 }
 
 /*
@@ -9863,11 +9869,15 @@ mono_aot_get_method_name (MonoCompile *cfg)
 		}
 	}
 
-	if (llvm_acfg->aot_opts.static_link)
+	if (llvm_acfg->aot_opts.static_link) {
 		/* Include the assembly name too to avoid duplicate symbol errors */
-		return g_strdup_printf ("%s_%s", llvm_acfg->assembly_name_sym, get_debug_sym (cfg->orig_method, "", llvm_acfg->method_label_hash));
-	else
+		char *tmp_debug_sym = get_debug_sym (cfg->orig_method, "", llvm_acfg->method_label_hash);
+		char *debug_sym = g_strdup_printf ("%s_%s", llvm_acfg->assembly_name_sym, tmp_debug_sym);
+		g_free (tmp_debug_sym);
+		return debug_sym;
+	} else {
 		return get_debug_sym (cfg->orig_method, "", llvm_acfg->method_label_hash);
+	}
 }
 
 static gboolean
@@ -15372,7 +15382,7 @@ emit_aot_image (MonoAotCompile *acfg)
 			} else {
 				cfg->asm_symbol = g_strdup_printf ("%s%sm_%x", acfg->temp_prefix, acfg->llvm_label_prefix, method_index);
 			}
-			cfg->asm_debug_symbol = cfg->asm_symbol;
+			cfg->asm_debug_symbol = g_strdup (cfg->asm_symbol);
 		}
 	}
 
diff --git a/src/mono/mono/mini/mini.c b/src/mono/mono/mini/mini.c
index e0a0a81d0a5c2..eb174000eabe7 100644
--- a/src/mono/mono/mini/mini.c
+++ b/src/mono/mono/mini/mini.c
@@ -1756,7 +1756,7 @@ mono_empty_compile (MonoCompile *cfg)
 	cfg->headers_to_free = NULL;
 
 	if (cfg->mempool) {
-	//mono_mempool_stats (cfg->mempool);
+		//mono_mempool_stats (cfg->mempool);
 		mono_mempool_destroy (cfg->mempool);
 		cfg->mempool = NULL;
 	}
@@ -1788,6 +1788,10 @@ mono_destroy_compile (MonoCompile *cfg)
 
 	mono_debug_free_method (cfg);
 
+	g_free (cfg->asm_symbol);
+	g_free (cfg->asm_debug_symbol);
+	g_free (cfg->llvm_method_name);
+
 	g_free (cfg->varinfo);
 	g_free (cfg->vars);
 	g_free (cfg->exception_message);
diff --git a/src/mono/mono/mini/seq-points.c b/src/mono/mono/mini/seq-points.c
index b998c6c86d97b..48388e08d5ab8 100644
--- a/src/mono/mono/mini/seq-points.c
+++ b/src/mono/mono/mini/seq-points.c
@@ -238,10 +238,13 @@ mono_save_seq_point_info (MonoCompile *cfg, MonoJitInfo *jinfo)
 		MonoJitMemoryManager *jit_mm = get_default_jit_mm ();
 		jit_mm_lock (jit_mm);
 		// FIXME: The lookup can fail if the method is JITted recursively though a type cctor
-		if (!g_hash_table_lookup (jit_mm->seq_points, cfg->method_to_register))
+		MonoSeqPointInfo *existing_seq_points = NULL;
+		if (!g_hash_table_lookup_extended (jit_mm->seq_points, cfg->method_to_register, NULL, (gpointer *)&existing_seq_points)) {
 			g_hash_table_insert (jit_mm->seq_points, cfg->method_to_register, cfg->seq_point_info);
-		else
+		} else {
 			mono_seq_point_info_free (cfg->seq_point_info);
+			cfg->seq_point_info = existing_seq_points;
+		}
 		jit_mm_unlock (jit_mm);
 
 		g_assert (jinfo);