Fix:

warning: implicit conversion of NULL constant to 'bool' [-Wnull-conversion]
--- src/tools/exravg.cpp.orig	2019-01-04 18:22:30.000000000 -0600
+++ src/tools/exravg.cpp	2026-03-29 04:40:17.000000000 -0500
@@ -75,7 +75,7 @@
     delete[] hrgba;
     } catch (const std::exception &e) {
         fprintf(stderr, "Unable to read image file \"%s\": %s", name, e.what());
-        return NULL;
+        return false;
     }
 
     return rgba;
--- src/tools/exrdiff.cpp.orig	2019-01-04 18:22:30.000000000 -0600
+++ src/tools/exrdiff.cpp	2026-03-29 04:40:23.000000000 -0500
@@ -145,7 +145,7 @@
     delete[] hrgba;
     } catch (const std::exception &e) {
         fprintf(stderr, "Unable to read image file \"%s\": %s", name, e.what());
-        return NULL;
+        return false;
     }
 
     return rgba;