diff --git a/i3-config-wizard/main.c b/i3-config-wizard/main.c
index 0c8c705a..988654d2 100644
--- a/i3-config-wizard/main.c
+++ b/i3-config-wizard/main.c
@@ -216,7 +216,7 @@ static const char *get_string(const char *identifier) {
 
 static void clear_stack(void) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].type == STACK_STR && stack[c].val.str != NULL)
+        if (stack[c].type == STACK_STR)
             free(stack[c].val.str);
         stack[c].identifier = NULL;
         stack[c].val.str = NULL;
diff --git a/libi3/dpi.c b/libi3/dpi.c
index a2c40319..9bb32b68 100644
--- a/libi3/dpi.c
+++ b/libi3/dpi.c
@@ -54,9 +54,7 @@ void init_dpi(void) {
     DLOG("Found Xft.dpi = %ld.\n", dpi);
 
 init_dpi_end:
-    if (resource != NULL) {
-        free(resource);
-    }
+    free(resource);
 
     if (database != NULL) {
         xcb_xrm_database_free(database);
diff --git a/libi3/font.c b/libi3/font.c
index 3dca8124..7be84ee0 100644
--- a/libi3/font.c
+++ b/libi3/font.c
@@ -224,9 +224,7 @@ i3Font load_font(const char *pattern, const bool fallback) {
                      error->error_code);
         }
     }
-    if (error != NULL) {
-        free(error);
-    }
+    free(error);
 
     font.pattern = sstrdup(pattern);
     LOG("Using X font %s\n", pattern);
@@ -275,8 +273,7 @@ void free_font(void) {
         case FONT_TYPE_XCB: {
             /* Close the font and free the info */
             xcb_close_font(conn, savedFont->specific.xcb.id);
-            if (savedFont->specific.xcb.info)
-                free(savedFont->specific.xcb.info);
+            free(savedFont->specific.xcb.info);
             break;
         }
         case FONT_TYPE_PANGO:
diff --git a/src/commands_parser.c b/src/commands_parser.c
index 98f06659..4299c008 100644
--- a/src/commands_parser.c
+++ b/src/commands_parser.c
@@ -157,7 +157,7 @@ static long get_long(const char *identifier) {
 // TODO move to a common util
 static void clear_stack(void) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].type == STACK_STR && stack[c].val.str != NULL)
+        if (stack[c].type == STACK_STR)
             free(stack[c].val.str);
         stack[c].identifier = NULL;
         stack[c].val.str = NULL;
diff --git a/src/config_parser.c b/src/config_parser.c
index 2d3f3bb9..9f972fed 100644
--- a/src/config_parser.c
+++ b/src/config_parser.c
@@ -171,7 +171,7 @@ static long get_long(const char *identifier) {
 
 static void clear_stack(void) {
     for (int c = 0; c < 10; c++) {
-        if (stack[c].type == STACK_STR && stack[c].val.str != NULL)
+        if (stack[c].type == STACK_STR)
             free(stack[c].val.str);
         stack[c].identifier = NULL;
         stack[c].val.str = NULL;
diff --git a/src/load_layout.c b/src/load_layout.c
index 32da9c47..5a340d2c 100644
--- a/src/load_layout.c
+++ b/src/load_layout.c
@@ -153,8 +153,7 @@ static int json_end_map(void *ctx) {
                 free(marks[i]);
             }
 
-            free(marks);
-            marks = NULL;
+            FREE(marks);
             num_marks = 0;
         }
 
diff --git a/src/util.c b/src/util.c
index a59283a8..594d2bb6 100644
--- a/src/util.c
+++ b/src/util.c
@@ -501,8 +501,7 @@ ssize_t slurp(const char *path, char **buf) {
     fclose(f);
     if ((ssize_t)n != stbuf.st_size) {
         ELOG("File \"%s\" could not be read entirely: got %zd, want %" PRIi64 "\n", path, n, (int64_t)stbuf.st_size);
-        free(*buf);
-        *buf = NULL;
+        FREE(*buf);
         return -1;
     }
     return (ssize_t)n;