tc6: fix implicit widening in pointer arithmetic (sync branch)#72
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tkummermehr wants to merge 1 commit intomainfrom
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tc6: fix implicit widening in pointer arithmetic (sync branch)#72tkummermehr wants to merge 1 commit intomainfrom
tkummermehr wants to merge 1 commit intomainfrom
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Cast uint16_t multipliers to size_t before multiplication with unsigned int constants in pointer offset calculations. Silences clang-tidy warnings about implicit widening of multiplication results when used as pointer offsets. Affected: register array pointer advancement in mk_ctrl_req and mk_secure_ctrl_req functions where (num_regs * 4u) and (num_regs * 8u) are used as array indices. Multiplication of uint16_t and uint results in unsigned int, which is implicitly widened to size_t when used as offset. Explicit cast makes the widening conversion clear. Finding: clang-tidy/bugprone-implicit-widening-of-multiplication-result at libtc6/src/tc6.c:1053,1094
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Summary
Fixes 2 clang-tidy
bugprone-implicit-widening-of-multiplication-resultwarnings in register buffer pointer arithmetic.Problem
Multiplication of
uint16_t num_regswith unsigned constants (4u,8u) results inunsigned int. When used as array offset in&dst[num_regs * 4u], the result is implicitly widened tosize_t, triggering implicit-widening warnings.Solution
Cast
num_regstosize_tbefore multiplication:(size_t)num_regs * 4u. Explicit cast clarifies the type promotion and silences the warning.Verification
Affected functions:
mk_ctrl_reqandmk_secure_ctrl_req. Register arrays are 32-bit fields;num_regs * 4/8fits safely insize_t. No behavior change.Closes findings from static-analysis scan.