clang/test/Preprocessor/embed_parameter_offset.c

   1 // RUN: %clang_cc1 -std=c23 %s --embed-dir=%S/Inputs -fsyntax-only -verify
   2
   3 const char data[] = {
   4 #embed <jk.txt>
   5 };
   6 const char offset_data[] = {
   7 #embed <jk.txt> clang::offset(1)
   8 };
   9 static_assert(sizeof(data) == 2);
  10 static_assert('j' == data[0]);
  11 static_assert('k' == data[1]);
  12 static_assert(sizeof(offset_data) == 1);
  13 static_assert('k' == offset_data[0]);
  14 static_assert(offset_data[0] == data[1]);
  15
  16 // Cannot have a negative offset.
  17 #embed <jk.txt> clang::offset(-1)
  18 // expected-error@-1 {{invalid value '-1'; must be positive}}
  19
  20 // If the offset is past the end of the file, the file should be considered
  21 // empty.
  22 #if __has_embed(<jk.txt> clang::offset(3)) != __STDC_EMBED_EMPTY__
  23 #error "__has_embed should return false when there's no data"
  24 #endif
  25
  26 // When the offset is past the end of the file, the resource is empty, so if_empty kicks in.
  27 const unsigned char buffer[] = {
  28 #embed <jk.txt> clang::offset(3) if_empty(1)
  29 };
  30 static_assert(sizeof(buffer) == 1);
  31 static_assert(buffer[0] == 1);
  32
  33 // However, prefix and suffix do not kick in.
  34 const unsigned char other_buffer[] = {
  35   1,
  36 #embed <jk.txt> clang::offset(3) prefix(2,) suffix(3)
  37 };
  38 static_assert(sizeof(other_buffer) == 1);
  39 static_assert(other_buffer[0] == 1);
  40
  41 // Ensure we can offset to zero (that's the default behavior)
  42 const unsigned char third_buffer[] = {
  43 #embed <jk.txt> clang::offset(0)
  44 };
  45 static_assert(sizeof(third_buffer) == 2);
  46 static_assert('j' == third_buffer[0]);
  47 static_assert('k' == third_buffer[1]);
  48
  49 // Test the offsets of a file with more than one character in it.
  50 const unsigned char fourth_buffer[] = {
  51 #embed <media/art.txt> clang::offset(24) limit(4)
  52 };
  53 static_assert(sizeof(fourth_buffer) == 4);
  54 static_assert('.' == fourth_buffer[0]);
  55 static_assert('-' == fourth_buffer[1]);
  56 static_assert('.' == fourth_buffer[2]);
  57 static_assert('\'' == fourth_buffer[3]);
  58
  59 // Ensure that an offset larger than what can fit into a 64-bit value is
  60 // rejected. This offset is fine because it fits in a 64-bit value.
  61 const unsigned char fifth_buffer[] = {
  62   1,
  63 #embed <jk.txt> clang::offset(0xFFFF'FFFF'FFFF'FFFF)
  64 };
  65 static_assert(sizeof(fifth_buffer) == 1);
  66 static_assert(1 == fifth_buffer[0]);
  67
  68 // But this one is not fine because it does not fit into a 64-bit value.
  69 const unsigned char sixth_buffer[] = {
  70 #embed <jk.txt> clang::offset(0xFFFF'FFFF'FFFF'FFFF'1)
  71 };
  72 // expected-error@-2 {{integer literal is too large to be represented in any integer type}}
  73
  74 // Ensure we diagnose duplicate parameters even if they're the same value.
  75 const unsigned char a[] = {
  76 #embed <jk.txt> clang::offset(1) prefix() clang::offset(1)
  77 // expected-error@-1 {{cannot specify parameter 'clang::offset' twice in the same '#embed' directive}}
  78 ,
  79 #embed <jk.txt> clang::offset(1) if_empty() clang::offset(2)
  80 // expected-error@-1 {{cannot specify parameter 'clang::offset' twice in the same '#embed' directive}}
  81 };
  82
  83 // Matches with C23 6.10.3.2p2, is documented as part of our extension.
  84 static_assert(
  85 #embed <jk.txt> clang::offset(defined(FOO))
  86   == 0); // expected-error {{expected expression}}
  87  /* expected-error@-2 {{'defined' cannot appear within this context}}
  88     pedantic-warning@-2 {{'clang::offset' is a Clang extension}}
  89   */