[MC/DC][branch coverage] trouble in handling macros from system headers with cast #131505
Description
Compiler explorer link.
test.c
// (1) macros defined in a system header #include <test.h> int buf[100]; int a, b, c; int main(void) { if ( FOO(buf) && a && b ) return 1; if ( BAR(buf) && a && b ) return 2; return 3; }test.h
#define FOO(x) ( x[0] && x[1] ) #define BAR(x) ( ((int *)x)[0] && ((int *)x)[1] ) // (2) castExpressions involving FOO or BAR exhibit different behaviors in terms of MC/DC: different numbers of conditions are reported
7| 1|int main(void) { 8| 1| if ( FOO(buf) && a && b ) ------------------------------- |---> MC/DC Decision Region (8:10) to (8:28) | | Number of Conditions: 4 | Condition C1 --> (8:10) | Condition C2 --> (8:10) | Condition C3 --> (8:22) | Condition C4 --> (8:27) | | Executed MC/DC Test Vectors: | | C1, C2, C3, C4 Result | 1 { F, -, -, - = F } | | C1-Pair: not covered | C2-Pair: not covered | C3-Pair: not covered | C4-Pair: not covered | MC/DC Coverage for Decision: 0.00% | ------------------------------- 9| 0| return 1; 10| 1| if ( BAR(buf) && a && b ) ------------------------------- |---> MC/DC Decision Region (10:10) to (10:28) | | Number of Conditions: 3 | Condition C1 --> (10:10) | Condition C2 --> (10:22) | Condition C3 --> (10:27) | | Executed MC/DC Test Vectors: | | C1, C2, C3 Result | 1 { F, -, - = F } | | C1-Pair: not covered | C2-Pair: not covered | C3-Pair: not covered | MC/DC Coverage for Decision: 0.00% | ------------------------------- 11| 0| return 2; 12| 1| return 3; 13| 1|} Real-world example: https://sources.debian.org/src/hostname/3.23%2Bnmu1/hostname.c/#L312
cc: @evodius96