[UIFontDescriptor initialize] may have been in progress in another thread when fork() was called

[erdemgezer]

Having interesting errors both on Mac and Ubuntu (Docker) while adding text on top of an image using ruby-vips.

text = Vips::Image.text(
        text_content,
        width: width,
        height: height,
        align: vips_align,
        font: font_name,
        fontfile: font_file,
        spacing: line_spacing
      )
image.composite(text, :over, x: x, y: y)

On my mac development environment, If I call this method from an ActiveJob, it fails with:

objc[25970]: +[UIFontDescriptor initialize] may have been in progress in another thread when fork() was called.
objc[25970]: +[UIFontDescriptor initialize] may have been in progress in another thread when fork() was called. We cannot safely call it or ignore it in the fork() child process. Crashing instead. Set a breakpoint on objc_initializeAfterForkError to debug.

Using of env var OBJC_DISABLE_INITIALIZE_FORK_SAFETY=yes fixes it as suggested in #155 (comment)

However, on Ubuntu docker environment I randomly get segmentation fault errors or floating point exception errors when running the from Rails console.

Everthing works fine if I don't use the .text method in both environments.

Mac stack
MacOS 15.3.1 (M2)
Ruby 3.3.5
Rails 7.2.1
vips-8.16.0

Ubuntu stack
Dockerized x86_64
Linux 116.202.15.119-1f5530ef76b3 6.8.0-54-generic
Using libvips42 package
Ruby 3.3.5
Rails 7.2.1

[jcupitt]

Hi @erdemgezer,

There have been some improvements to locking in text rendering in recent libvipses. Have you tried your Ubuntu example with current stable libvips (8.16.1)?

Text rendering is extremely complex, unfortunately, and interacts with a huge number of different libraries and system components on the various platforms :(

[erdemgezer]

Hi @erdemgezer,

There have been some improvements to locking in text rendering in recent libvipses. Have you tried your Ubuntu example with current stable libvips (8.16.1)?

Text rendering is extremely complex, unfortunately, and interacts with a huge number of different libraries and system components on the various platforms :(

Hi @jcupitt ,
Thanks for letting me know about the latest stable release. I used to install libvips via apt-get from the Dockerfile but I believe I need to build it from source to be able to use the latest version. I'll give it a go and share the results.