have_func: checking for rb_enc_raise() in ruby.h... -------------------- yes

"gcc -o conftest -I/usr/include/ruby-2.6.0/x86_64-linux -I/usr/include/ruby-2.6.0/ruby/backward -I/usr/include/ruby-2.6.0 -I. -D_FORTIFY_SOURCE=2   -march=x86-64 -mtune=generic -O2 -pipe -fstack-protector-strong -fno-plt -fPIC conftest.c  -L. -L/usr/lib -L. -Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now -fstack-protector-strong -rdynamic -Wl,-export-dynamic     -lruby  -lm   -lc"
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: int main(int argc, char **argv)
4: {
5:   return 0;
6: }
/* end */

"gcc -o conftest -I/usr/include/ruby-2.6.0/x86_64-linux -I/usr/include/ruby-2.6.0/ruby/backward -I/usr/include/ruby-2.6.0 -I. -D_FORTIFY_SOURCE=2   -march=x86-64 -mtune=generic -O2 -pipe -fstack-protector-strong -fno-plt -fPIC conftest.c  -L. -L/usr/lib -L. -Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now -fstack-protector-strong -rdynamic -Wl,-export-dynamic     -lruby  -lm   -lc"
conftest.c: In function ‘t’:
conftest.c:16:57: error: ‘rb_enc_raise’ undeclared (first use in this function); did you mean ‘rb_exc_raise’?
 int t(void) { void ((*volatile p)()); p = (void ((*)()))rb_enc_raise; return !p; }
                                                         ^~~~~~~~~~~~
                                                         rb_exc_raise
conftest.c:16:57: note: each undeclared identifier is reported only once for each function it appears in
checked program was:
/* begin */
 1: #include "ruby.h"
 2: 
 3: #include <ruby.h>
 4: 
 5: /*top*/
 6: extern int t(void);
 7: int main(int argc, char **argv)
 8: {
 9:   if (argc > 1000000) {
10:     int (* volatile tp)(void)=(int (*)(void))&t;
11:     printf("%d", (*tp)());
12:   }
13: 
14:   return 0;
15: }
16: int t(void) { void ((*volatile p)()); p = (void ((*)()))rb_enc_raise; return !p; }
/* end */

"gcc -o conftest -I/usr/include/ruby-2.6.0/x86_64-linux -I/usr/include/ruby-2.6.0/ruby/backward -I/usr/include/ruby-2.6.0 -I. -D_FORTIFY_SOURCE=2   -march=x86-64 -mtune=generic -O2 -pipe -fstack-protector-strong -fno-plt -fPIC conftest.c  -L. -L/usr/lib -L. -Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now -fstack-protector-strong -rdynamic -Wl,-export-dynamic     -lruby  -lm   -lc"
checked program was:
/* begin */
 1: #include "ruby.h"
 2: 
 3: #include <ruby.h>
 4: 
 5: /*top*/
 6: extern int t(void);
 7: int main(int argc, char **argv)
 8: {
 9:   if (argc > 1000000) {
10:     int (* volatile tp)(void)=(int (*)(void))&t;
11:     printf("%d", (*tp)());
12:   }
13: 
14:   return 0;
15: }
16: extern void rb_enc_raise();
17: int t(void) { rb_enc_raise(); return 0; }
/* end */

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