os/mac/ruby_mach: don't hide actual parse errors

The current approach of suppressing all output regardless of what the
error is makes it very hard to debug any issues and misread but valid
Mach-O files will be silently interpreted as non-Mach-O files instead.

Prefer to fail if we are a Homebrew developer or running on the bot
(`HOMEBREW_DEVELOPER=1`), so that problems will be noticed and fixed
before the silent failure leads to hard-to-diagnose user problems.

Closes Homebrew/homebrew#48817.

Signed-off-by: Martin Afanasjew <martin@afanasjew.de>

1 files changed, 8 insertions, 0 deletions

diff --git a/Library/Homebrew/os/mac/ruby_mach.rb b/Library/Homebrew/os/mac/ruby_mach.rb
index 3cd0ac0b9..adef7b661 100644
--- a/Library/Homebrew/os/mac/ruby_mach.rb
+++ b/Library/Homebrew/os/mac/ruby_mach.rb
@@ -41,7 +41,15 @@ module RubyMachO
       end
 
       mach_data
+    rescue MachO::NotAMachOError
+      # Silently ignore errors that indicate the file is not a Mach-O binary ...
+      []
     rescue
+      # ... but complain about other (parse) errors for further investigation.
+      if ARGV.homebrew_developer?
+        onoe "Failed to read Mach-O binary: #{self}"
+        raise
+      end
       []
     end
   end