gcc/testsuite/gcc.dg/Wstringop-overflow-68.c

/* PR tree-optimization/97027 - missing warning on buffer overflow storing
   a larger scalar into a smaller array
   Verify overflow by aggregate stores.
   { dg-do compile }
   { dg-options "-O2 -fno-tree-vectorize" } */

#define A(N) (A ## N)
#define Ac1 (AC1){ 0 }
#define Ac2 (AC2){ 0, 1 }
#define Ac4 (AC4){ 0, 1, 2, 3 }
#define Ac8 (AC8){ 0, 1, 2, 3, 4, 5, 6, 7 }
#define Ac16 (AC16){ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 }

typedef struct AC1 { char a[1]; } AC1;
typedef struct AC2 { char a[2]; } AC2;
typedef struct AC3 { char a[3]; } AC3;
typedef struct AC4 { char a[4]; } AC4;
typedef struct AC5 { char a[5]; } AC5;
typedef struct AC8 { char a[8]; } AC8;
typedef struct AC16 { char a[16]; } AC16;

extern char a1[1], a2[2], a3[3], a4[4], a5[5], a6[6], a7[7], a8[8], a15[15];

extern AC1 ac1;
extern AC2 ac2;
extern AC4 ac4;
extern AC8 ac8;
extern AC16 ac16;

extern AC1 fac1 (void);
extern AC2 fac2 (void);
extern AC4 fac4 (void);
extern AC8 fac8 (void);
extern AC16 fac16 (void);

void nowarn (void)
{
  *(AC1*)a1 = Ac1;
  *(AC2*)a2 = Ac2;
  *(AC4*)a4 = Ac4;
  *(AC4*)a5 = Ac4;
  *(AC4*)a6 = Ac4;
  *(AC4*)a7 = Ac4;
  *(AC8*)a8 = Ac8;
  *(AC8*)a15 = Ac8;
}

void warn_comp_lit_zero (void)
{
  *(AC2*)a1 = (AC2){ }; // { dg-warning "writing 2 bytes into a region of size 1" }
  *(AC4*)a2 = (AC4){ }; // { dg-warning "writing 4 bytes into a region of size 2" }
  *(AC4*)a3 = (AC4){ }; // { dg-warning "writing 4 bytes into a region of size 3" }
  *(AC8*)a4 = (AC8){ }; // { dg-warning "writing 8 bytes into a region of size 4" }
  *(AC8*)a7 = (AC8){ }; // { dg-warning "writing 8 bytes into a region of size 7" }
  *(AC16*)a15 = (AC16){ };// { dg-warning "writing 16 bytes into a region of size 15" }
}

void warn_comp_lit (void)
{
  /* Ideally only one warning would be issued for each of the stores
     mentioning the size of the rest of the source being assigned to
     the destination that doesn't fit.  But without vectorization
     the assignment is a series of one-character stores, except in
     the first instance multiple warnings end up being issued for
     each assignment, each saying "writing 1 byte into a region of
     size 0".  That's suboptimal and should be improved.  See also
     PR 92110.  */
  *(AC2*)a1 = Ac2;      // { dg-warning "writing (2 bytes|1 byte) into a region of size (1|0)" "pr101475" }
  *(AC4*)a2 = Ac4;      // { dg-warning "writing (4 bytes|1 byte) into a region of size (2|0)" "pr101475" }
  *(AC4*)a3 = Ac4;      // { dg-warning "writing (4 bytes|1 byte) into a region of size (3|0)" "pr101475" }
  *(AC8*)a4 = Ac8;      // { dg-warning "writing (8 bytes|1 byte) into a region of size (4|0)" "pr101475" }
  *(AC8*)a7 = Ac8;      // { dg-warning "writing (8 bytes|1 byte) into a region of size (7|0)" "pr101475" }
  *(AC16*)a15 = Ac16;   // { dg-warning "writing (16 bytes|1 byte) into a region of size (15|0)" "pr101475" }
}

void warn_aggr_decl (void)
{
  *(AC2*)a1 = ac2;      // { dg-warning "writing 2 bytes into a region of size 1" }
  *(AC4*)a2 = ac4;      // { dg-warning "writing 4 bytes into a region of size 2" }
  *(AC4*)a3 = ac4;      // { dg-warning "writing 4 bytes into a region of size 3" }
  *(AC8*)a4 = ac8;      // { dg-warning "writing 8 bytes into a region of size 4" }
  *(AC8*)a7 = ac8;      // { dg-warning "writing 8 bytes into a region of size 7" }
  *(AC16*)a15 = ac16;   // { dg-warning "writing 16 bytes into a region of size 15" }
}

void warn_aggr_parm (AC2 pc2, AC4 pc4, AC8 pc8, AC16 pc16)
{
  *(AC2*)a1 = pc2;      // { dg-warning "writing 2 bytes into a region of size 1" }
  *(AC4*)a2 = pc4;      // { dg-warning "writing 4 bytes into a region of size 2" }
  *(AC4*)a3 = pc4;      // { dg-warning "writing 4 bytes into a region of size 3" }
  *(AC8*)a4 = pc8;      // { dg-warning "writing 8 bytes into a region of size 4" }
  *(AC8*)a7 = pc8;      // { dg-warning "writing 8 bytes into a region of size 7" }
  *(AC16*)a15 = pc16;   // { dg-warning "writing 16 bytes into a region of size 15" }
}

void warn_aggr_func (void)
{
  *(AC2*)a1 = fac2 ();  // { dg-warning "writing 2 bytes into a region of size 1" }
  *(AC4*)a2 = fac4 ();  // { dg-warning "writing 4 bytes into a region of size 2" }
  *(AC4*)a3 = fac4 ();  // { dg-warning "writing 4 bytes into a region of size 3" }
  *(AC8*)a4 = fac8 ();  // { dg-warning "writing 8 bytes into a region of size 4" }
  *(AC8*)a7 = fac8 ();  // { dg-warning "writing 8 bytes into a region of size 7" }
  *(AC16*)a15 = fac16 ();// { dg-warning "writing 16 bytes into a region of size 15" }

  extern AC2 fac2_x ();

  *(AC2*)a1 = fac2_x ();  // { dg-warning "writing 2 bytes into a region of size 1" }

  extern AC2 fac2_p (char*);

  *(AC2*)a1 = fac2_p (0); // { dg-warning "writing 2 bytes into a region of size 1" }
}