GCC -Wshadow lambda capture warning inconsistency

Does GCC's -Wshadow warn on lambda captures that shadow outer variables?

0 reputation · 16 Jul 2025, 18:04 UTC

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Goal

The goal is to determine whether the -Wshadow option should emit a warning when a C++ lambda capture introduces a name that hides an outer variable.

Constraints

The GCC manual states that -Wshadow applies only to C, yet GCC 10 produces a warning for such lambda captures while GCC 12 does not, and the bug tracker lists this discrepancy as an open issue.

Questions

Which GCC versions emit the warning for lambda captures that shadow outer variables?
Is the -Wshadow warning intended for C++ code or only for C?
How does -Wextra interact with -Wshadow to produce duplicate warnings for the same shadowed name?

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Does GCC's -Wshadow warn on lambda captures that shadow outer variables?

Goal

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