Added conditional support of noexcept to fix IAR support

[ockeydockey]

When exceptions are disabled in IAR 8.x, the keyword noexcept in any form will cause a build error.

Adding back in the conditional support for the noexcept keyword based on the etl_profile settings.

[ockeydockey]

@jwellbelove, if you don't like using this flag, I can also recommend using the feature test macro in the C++ standard:

#if defined(__cpp_exceptions)

[coderabbitai]

Walkthrough

The change updates macro definitions for exception specifications in the ETL C++11 configuration. ETL_NOEXCEPT and ETL_NOEXCEPT_EXPR(...) are now conditionally defined based on ETL_USING_EXCEPTIONS. When exceptions are enabled, they expand to noexcept and noexcept(VA_ARGS) respectively; when disabled, they expand to empty. This replaces prior unconditional definitions of these macros.

Pre-merge checks and finishing touches

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title Check	✅ Passed	The title clearly summarises the primary change of adding conditional noexcept support to address IAR build issues with disabled exceptions. It is concise, specific, and directly reflects the modifications made in the pull request.
Description Check	✅ Passed	The description clearly explains the IAR build error caused by noexcept when exceptions are disabled and states that conditional support is being restored based on the etl_profile, directly matching the implemented change.
Docstring Coverage	✅ Passed	No functions found in the changes. Docstring coverage check skipped.

✨ Finishing touches

• 📝 Generate Docstrings

🧪 Generate unit tests

• Create PR with unit tests
• Post copyable unit tests in a comment

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[coderabbitai]

Actionable comments posted: 1

📜 Review details

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📥 Commits

Reviewing files that changed from the base of the PR and between f9cf20d and efb8771.

📒 Files selected for processing (1)

• include/etl/platform.h (1 hunks)

🧰 Additional context used

📓 Path-based instructions (1)

include/etl/*.h

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[coderabbitai]

🛠️ Refactor suggestion | 🟠 Major

🧩 Analysis chain

Conditional noexcept correctly implements IAR workaround.

The conditional definition properly addresses IAR 8.x's rejection of the noexcept keyword when exceptions are disabled. The logic is sound: when ETL_USING_EXCEPTIONS is true, the macros expand to standard noexcept specifications; when false, they expand to empty, avoiding the IAR build error.

Verify that this change doesn't adversely affect other supported compilers. Run the following script to check for any direct usage of noexcept (not via macros) in the codebase:

---

🏁 Script executed:

#!/bin/bash
# Description: Find any direct usage of noexcept keyword that might need similar treatment

# Search for noexcept keyword usage outside of macro definitions
rg -n --type=cpp --type=c -g '!platform.h' '\bnoexcept\b' -C2

Length of output: 148

---

🏁 Script executed:

#!/bin/bash
# Search for direct usages of noexcept outside the macro definitions,
# excluding include/etl/platform.h
rg -n --type=c --type=cpp '\bnoexcept\b' -C2 --glob '!include/etl/platform.h'

Length of output: 148

---

🏁 Script executed:

#!/bin/bash
# Search for direct usages of noexcept outside platform.h without type filters
rg -n 'noexcept\b' -C2 --glob '!include/etl/platform.h'

Length of output: 148

---

🏁 Script executed:

#!/bin/bash
# Broad search for any direct usage of noexcept in the codebase
rg -n 'noexcept\b' -C2

Length of output: 41748

---

Use ETL_NOEXCEPT instead of raw noexcept
Direct noexcept occurrences (e.g. in test files and include/etl/data.h) bypass the new conditional and may still break IAR when exceptions are disabled. Replace them with ETL_NOEXCEPT or ETL_NOEXCEPT_EXPR as appropriate.

🤖 Prompt for AI Agents

In include/etl/platform.h around lines 334 to 340, raw uses of the C++ keyword
noexcept are still present elsewhere (e.g. test files and include/etl/data.h)
and will bypass the ETL conditional macros when exceptions are disabled; search
for all direct occurrences of "noexcept" and replace them with ETL_NOEXCEPT, and
replace instances that use noexcept(...) with ETL_NOEXCEPT_EXPR(...), making
sure the file includes include/etl/platform.h (or otherwise has those macros
visible) so builds targeting IAR with ETL_USING_EXCEPTIONS disabled use the
conditional definitions.