Test suite uses portable weak symbol scanning for Darwin C++ tests.
GCC's C++ test suite now employs portable `scan-weak` and `scan-not-weak` directives for weak symbol checks, especially on Darwin.
This commit refactors a C++ test in GCC’s test suite to use the scan-weak and scan-not-weak directives, improving its portability, particularly for Darwin targets. Previously, the test g++.dg/reflect/visibility1.C might have required extensive modifications to function correctly on Darwin due to differences in how weak symbols are handled. By leveraging these portability helpers, the test suite can now reliably verify weak symbol behavior across different operating systems, reducing maintenance overhead and ensuring consistent testing results.
In Details
Weak symbols are linker features that allow multiple definitions of a symbol, with the linker choosing one (usually the non-weak one) or allowing a default if no strong definition exists. On Darwin (macOS), the behavior and representation of weak symbols in object files can differ from other Unix-like systems. This commit updates a C++ test for reflection and visibility (g++.dg/reflect/visibility1.C) to use scan-weak and scan-not-weak directives. These abstract the low-level details of checking for weak symbol presence, making the test robust to platform differences and the various `mac…
For Context
In computer programming, a \"symbol\" is like a name for a function or a variable. Sometimes, a program might have multiple versions of the same symbol, and the system needs to decide which one to use. \"Weak symbols\" are a way to tell the system that a particular version of a symbol can be overridden by another, stronger one if it exists. This update to GCC's automated tests makes it easier to check how these weak symbols behave across different operating systems, especially on Apple's macOS (Darwin). By using special commands that automatically adapt to the system's specifics, the tests become more reliable and easier to maintain, ensuring that programs using weak symbols work correctly on various platforms.