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Comment by thealistra | Hacker News Reader

Thanks to apple we have a compiler alternative, that actually helps with this problem.

  alistra@bialobrewy ~ % clang -Weverything 1.c
  1.c:6:8: warning: comparison of integers of different signs: 'int' and 'unsigned int' [-Wsign-compare]
          if(-1 < x)
             ~~ ^ ~

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gcc also has -Wsign-compare option that warns about such comparisons.

GCC prints a similar warning with `-Wall`

actually with -Wextra

  alistra@bialobrewy ~ % gcc -Wextra 1.c
  1.c: In function ‘main’:
  1.c:6:8: warning: comparison between signed and unsigned integer expressions
  alistra@bialobrewy ~ % gcc -Wall 1.c  
  alistra@bialobrewy ~ %

Yes, for some reason in gcc, -Wall enables -Wsign-compare in C++ mode, but not in C mode. Maybe too much existing C code uses those kinds of comparisons?

The fact the code uses those kinds of comparisons, doesn't mean, that it uses it properly.

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