fix(libhsakmt): Define _GNU_SOURCE before libhsakmt.h include

[dayatsin-amd]

Summary

Move #define _GNU_SOURCE to the top of hsakmtmodel.c, before all includes, and remove the redundant #define __USE_GNU. _GNU_SOURCE must be defined before any system header is pulled in; hsakmtmodel.h, hsakmt_drm.h, and libhsakmt.h all transitively include libc/drm headers. Defining it after those includes breaks GNU extension visibility (e.g. secure_getenv) and causes compile errors in strict or sanitizer builds.

JIRA ID

JIRA ID : ROCM-26861

Test plan

Tested on dayatsin-test-01 (Ubuntu 24.04, amdclang 23.0.0 from /opt/rocm), including after removing __USE_GNU (c651d3f278):

• Build libhsakmt / rocr-runtime with ASAN enabled (-DADDRESS_SANITIZER=ON -DTHEROCK_SANITIZER=ASAN) — full build succeeded (libhsa-runtime64.so produced)
• Build with amdclang from TheRock/ROCm toolchain — Release hsakmt target succeeded
• Verify hsakmtmodel.c compiles without _GNU_SOURCE ordering warnings/errors — no errors in either ASAN or Release builds

[dayatsin-amd]

Test results (dayatsin-test-01)

Host: Ubuntu 24.04.3 LTS, amdclang 23.0.0 (/opt/rocm/lib/llvm/bin/amdclang)

Test	Result
ASAN full rocr-runtime build (-DADDRESS_SANITIZER=ON -DTHEROCK_SANITIZER=ASAN)	PASS — libhsa-runtime64.so linked successfully
Release hsakmt build (amdclang, no sanitizer)	PASS — hsakmtmodel.c.o compiled cleanly
hsakmtmodel.c _GNU_SOURCE / secure_getenv errors	None

Note: the initial commit only moved _GNU_SOURCE above libhsakmt.h; ASAN build on this host still failed because hsakmtmodel.h/hsakmt_drm.h pull in drm/amdgpu headers first. Follow-up commit e982b6d89d moves _GNU_SOURCE before all includes (matching openclose.c).

[therock-pr-bot]

❌ PR Check — Action Required

Check	Status	Details
🌿 Branch Name	✅ Pass	—
📝 PR Title/Description	✅ Pass	—
⛔ Forbidden Files	✅ Pass	—
🧪 Unit Test	❌ Fail	Error: Source/code files changed without an accompanying unit test. Expected: add at least one test file named like test_<name>.py / test_<name>.cpp (or <name>_test.*). Current: code file(s) changed: projects/rocr-runtime/libhsakmt/src/hsakmtmodel.c; no test file found
🔎 pre-commit	⏳ Pending	⏳ Still running…
🚫 Draft PR	🔜 To Be Enabled	—
🚩 Feature Flag	🔜 To Be Enabled	—
📊 Code Coverage	🔜 To Be Enabled	—

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🚫 Please fix the failed policies

• ❌ Unit Test

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[therock-pr-bot]

🚫 Please fix the failed policies before requesting reviews.

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• ❌ Unit Test

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Once all policies pass, the label will be removed automatically.

[cfreeamd]

🤖 AI-assisted pre-review (for @cfreeamd) — projects/rocr-runtime/libhsakmt/src/hsakmtmodel.c reviewed.

[dayatsin-amd]

Re-test after removing __USE_GNU (c651d3f278)

Host: dayatsin-test-01, Ubuntu 24.04.3 LTS, amdclang 23.0.0

Test	Result
ASAN full rocr-runtime build	PASS
Release hsakmt build	PASS
hsakmtmodel.c compile errors	None

_GNU_SOURCE alone is sufficient; __USE_GNU is redundant with it defined at the top of the TU.