https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63417
Bug ID: 63417 Summary: scanf: problem handling %hhd format Product: gcc Version: 4.8.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: subc2 at wp dot pl The following code runs properly on any UNIX-like operating system, but under Windows with GCC up to the version 4.8.1 (ports: MinGW, MinGW-w64, TDM-GCC) gives wrong results. file.c: #include <stdio.h> int main() { int logical = 1; signed char s_char; scanf("%hhd", &s_char); if (s_char == 0) logical = s_char; printf("%d", logical); return 0; } C:\> gcc -std=gnu99 file.c C:\> a.exe 0 0 C:\> a.exe 1 0 C:\> a.exe 2 0 What's even more interesting, after compiling this code magic.c: #include <stdio.h> int main() { int logical = 1; signed char s_char; scanf("%hhd", &s_char); if (s_char == 0) { int nothing = 0; logical = s_char; } printf("%d", logical); return 0; } C:\> gcc -std=gnu99 magic.c C:\> a.exe 0 0 C:\> a.exe 1 1 C:\> a.exe 2 1 everything is OK.