Avoid defined but not used warning in yyjson.c
#498
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bryceschober
commented
Sep 12, 2025
bryceschober
commented
```
./src/yyjson.c:4308:18: warning: ‘f64_pow10_table’ defined but not used [-Wunused-const-variable=]
4308 | static const f64 f64_pow10_table[] = {
| ^~~~~~~~~~~~~~~
```
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Summary of Changes
Hello @bryceschober, I'm Gemini Code Assist1! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!
This pull request resolves a specific compiler warning in 'src/yyjson.c' where the 'f64_pow10_table' was being defined but not used under certain compilation configurations. The change conditionally compiles this table, ensuring it is only included when the 'YYJSON_DOUBLE_MATH_CORRECT' macro is active, thus eliminating the warning without impacting the library's functionality.
Highlights
- Compiler Warning Resolution: Addressed a 'defined but not used' compiler warning for the 'f64_pow10_table' in 'src/yyjson.c'.
- Conditional Compilation: Implemented conditional compilation for 'f64_pow10_table' using '#if YYJSON_DOUBLE_MATH_CORRECT' to ensure it is only defined when actively used.
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Code Review
This pull request correctly addresses the 'defined but not used' warning for f64_pow10_table by wrapping its definition in the YYJSON_DOUBLE_MATH_CORRECT preprocessor directive. The fix is appropriate as the table is only used when this macro is enabled. I have one minor suggestion for further improvement to enhance code organization.
| @@ -4305,9 +4305,11 @@ static_inline u64 diy_fp_to_ieee_raw(diy_fp fp) { | |||
| #define F64_POW10_EXP_MAX_EXACT 22 | |||
|
|
|||
| /** Cached pow10 table. */ | |||
| #if YYJSON_DOUBLE_MATH_CORRECT | |||
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This is a good fix. For better code organization and to prevent potential future warnings about unused macros, consider also moving the definition of F64_POW10_EXP_MAX_EXACT (and its comment) from line 4305 inside this #if block, as it is only used when YYJSON_DOUBLE_MATH_CORRECT is enabled.
