runtime/cgo: add assertions for safe stack retrieval on unix

[froz42]

runtime/cgo: add assertions for safe stack retrieval on Unix

This change introduces assertions (assert()) to verify the return
values of pthread function calls in gcc_stack_unix.c. This improves
error detection and ensures failures in stack attribute retrieval are
caught early.

Changes:

• Added #include <assert.h> to include the assert() function.
• Wrapped pthread_attr_init, pthread_getattr_np, pthread_attr_get_np,
  and pthread_attr_getstack calls with assert() to ensure successful
  execution.
• This change enhances reliability, particularly in cases where these
  functions might fail silently.

Rationale:

• Ensuring pthread functions execute successfully prevents undefined
  behavior caused by uninitialized or incorrect stack attributes.
• The use of assert() helps catch errors in debug builds, aiding in
  troubleshooting potential issues early in development.

Testing:

• Verified that compilation succeeds without warnings or errors.
• Ensured that assertions do not trigger in normal execution scenarios.
• Manually tested on supported platforms to confirm expected behavior.

Fixes #71896

Change-Id: Ice10a4b506466e05720d7d45dc609bba75c49109
GitHub-Last-Rev: 0302d11
GitHub-Pull-Request: #71897

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[gopherbot]

Message from Gopher Robot:

Patch Set 1:

(1 comment)

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Patch Set 1:

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