gcc/clang "static assertion failed" in CI
static_assert checks a compile-time condition and fails the build with its message when false. It is an intentional guard - a trait, size, or version requirement was not met.
What this error means
The build stops at a static_assert with its custom message, often from a library enforcing a type trait, integer width, or standard version.
gcc
traits.h:18:3: error: static assertion failed: T must be trivially copyable
18 | static_assert(std::is_trivially_copyable_v<T>, "T must be trivially copyable");
| ^~~~~~~~~~~~~Common causes
How to fix it
Satisfy the asserted condition
- Read the static_assert message - it states the exact requirement.
- Change the type or configuration so the predicate holds.
gcc
// assert wants trivially copyable: remove the custom destructor,
// or use a different storage type that satisfies the trait.How to prevent it
- Honor the documented constraints of the templates you instantiate; static_assert turns a violated requirement into a clear compile-time message.
Frequently asked questions
What causes ""static assertion failed""?
The build stops at a static_assert with its custom message, often from a library enforcing a type trait, integer width, or standard version.
How do I fix "static assertion failed"?
Satisfy the asserted condition
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