Misc #16025: 'st_check_for_sizeof_st_index_t' declared as array with a negative size (emscripten)

• Status: Assigned
• Assignee: nobu (Nobuyoshi Nakada)

[vadimp (Vadim Peretokin)]

Compilation of st.h with Emscripten 1.38.30 fails:

st.h:65:45: error: 'st_check_for_sizeof_st_index_t' declared as an
      array with a negative size
typedef char st_check_for_sizeof_st_index_t[SIZEOF_VOIDP == (int)sizeof(st_index_t) ? 1 : -1];
                                            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3rdparty/edbee-lib/vendor/onig/config.h:109:22: note: expanded from macro 'SIZEOF_VOIDP'
#define SIZEOF_VOIDP 8
                     ^
1 error generated.
shared:ERROR: compiler frontend failed to generate LLVM bitcode, halting
Makefile:36871: recipe for target 'regcomp.o' failed

Both sizeof are set to 8:

onig$ cat config.h | grep SIZEOF_LONG
#define SIZEOF_LONG 8
#define SIZEOF_LONG_LONG 8

Is there a way to fix this issue or add a workaround for emscripten (__EMSCRIPTEN__)?

[nobu (Nobuyoshi Nakada)]

vadimp (Vadim Peretokin) wrote:

3rdparty/edbee-lib/vendor/onig/config.h:109:22: note: expanded from macro 'SIZEOF_VOIDP'

What is this file?
Do you mix different oniguruma?

[k_takata (Ken Takata)]

Original discussion at here: https://github.com/k-takata/Onigmo/issues/130
I think it's better to fix this in Ruby rather than in Onigmo.

I can suggest two ways.

1. Add #ifndef around st_check_for_sizeof_st_index_t

--- a/include/ruby/st.h
+++ b/include/ruby/st.h
@@ -55,7 +55,9 @@ typedef st_data_t st_index_t;
 typedef int st_compare_func(st_data_t, st_data_t);
 typedef st_index_t st_hash_func(st_data_t);
 
+#ifndef __EMSCRIPTEN__
 typedef char st_check_for_sizeof_st_index_t[SIZEOF_VOIDP == (int)sizeof(st_index_t) ? 1 : -1];
+#endif
 #define SIZEOF_ST_INDEX_T SIZEOF_VOIDP
 
 struct st_hash_type {

2. Remove st_check_for_sizeof_st_index_t

The size of void* and long or long long are already checked at here:
https://github.com/ruby/ruby/blob/8c6f1715f03e0322c96d614a42c30bee0b7790eb/include/ruby/st.h#L21-L27
Checking the size of st_index_t might be redundant.

[ko1 (Koichi Sasada)]

• Status changed from Open to Assigned
• Assignee set to nobu (Nobuyoshi Nakada)

[nobu (Nobuyoshi Nakada)]

k_takata (Ken Takata) wrote:

2. Remove st_check_for_sizeof_st_index_t

The size of void* and long or long long are already checked at here:
https://github.com/ruby/ruby/blob/8c6f1715f03e0322c96d614a42c30bee0b7790eb/include/ruby/st.h#L21-L27
Checking the size of st_index_t might be redundant.

This failure means the size of st_index_t doesn't equal the size of void*, so this check was not redundant actually.