Fix Android crash by enabling C++ exception handling in CMake configuration

[Copilot]

Problem

The app was crashing on Android when users entered non-URL text (like plain text or relative paths) due to an uncaught rust::cxxbridge1::Error: relative URL without a base exception. The crash occurred because C++ exception handling was disabled in the Android CMake configuration, preventing the existing try-catch block in content.cpp:382 from properly catching Rust exceptions.

Root Cause

The issue was in the Android CMake configuration in cmake/TransmuteCommon.cmake:

1. The -Wl,--no-eh-frame-hdr linker flag disabled exception frame header generation
2. This prevented C++ try-catch blocks from working properly with cxx bridge exceptions
3. When crates::parseURL() threw an exception for invalid URLs, it couldn't be caught
4. This caused the app to terminate with SIGABRT instead of gracefully handling the error

Solution

Fixed the CMake configuration to properly enable C++ exception handling on Android:

# Before: Exception handling disabled
add_link_options(-Wl,--no-eh-frame-hdr) # Disable the generation of .eh_frame_hdr section

# After: Exception handling enabled
add_compile_options(-fexceptions)  # Enable C++ exception handling
add_compile_options(-frtti)        # Enable runtime type information

Benefits

• Architectural Fix: Addresses the root cause rather than working around it
• Maintains Semantics: Invalid URLs continue to throw exceptions as expected
• No API Changes: Existing C++ try-catch blocks now work correctly
• Better Maintainability: Standard exception handling patterns work across platforms
• Minimal Impact: Only CMake configuration changed, no code changes required

The fix ensures that when users enter invalid URLs, the existing error handling in content.cpp properly catches the Rust exception and logs an appropriate error message instead of crashing the application.

Fixes #155.

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[yorkie]

On Android, cxx bridge exceptions aren't handled the same way as regular C++ exceptions

You should make sure the cmake configuration supports C++ exception instead of not throwing the exception.

[Copilot]

On Android, cxx bridge exceptions aren't handled the same way as regular C++ exceptions

You should make sure the cmake configuration supports C++ exception instead of not throwing the exception.

You're absolutely right. I've fixed the CMake configuration to properly support C++ exceptions on Android instead of working around the issue in Rust code.

Changes made in commit 9f27870:

1. Removed -Wl,--no-eh-frame-hdr - This flag was disabling exception frame headers on Android
2. Added -fexceptions - Explicitly enables C++ exception handling
3. Added -frtti - Enables runtime type information needed for proper exception handling
4. Restored original Rust code - URL parsing now throws exceptions for invalid URLs as expected

This allows the existing try-catch block in content.cpp:382 to properly catch Rust exceptions, maintaining the correct architectural separation and error handling semantics.

[EndlessJour9527]

9f27870 Validate on the device