Silence -Wstringop-truncation#55
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GCC 15.2.0 warns...
tests/fct.h:267:5: warning: ‘__builtin_strncpy’ specified bound 256 equals destination size [-Wstringop-truncation]
267 | strncpy(dst, src, num);
| ^
...because it dislikes writing a length-N src to a length-N dst.
Immediately thereafter there's an assignment, dst[num-1] = '\0'
to avoid the unbounded string concern. However, GCC does not
notice that and still issues the warning. Slightly rework
the statements here to avoid the warning without changing
the behavior. Routine continues to write at most a length N-1,
null-terminated string into the buffer.
RhysU
commented
Jan 16, 2026
| #endif | ||
| strncpy(dst, src, num-1); | ||
| dst[num-1] = '\0'; | ||
| #endif |
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Okay to move this final write inside the #endif because of the _TRUNCATE flag on the other half of the #ifdef.
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GCC 15.2.0 warns...
...because it dislikes writing a length-N src to a length-N dst. Immediately thereafter there's an assignment, dst[num-1] = '\0' to avoid the unbounded string concern. However, GCC does not notice that and still issues the warning. Slightly rework the statements here to avoid the warning without changing the behavior. Routine continues to write at most a length N-1, null-terminated string into the buffer.