4 files changed, 8 insertions, 0 deletions
diff --git a/include/alloca.h b/include/alloca.h
index fe70c36..76e027f 100644
--- a/include/alloca.h
+++ b/include/alloca.h
@@ -17,6 +17,7 @@
  */
 #ifndef _ALLOCA_H
 #define _ALLOCA_H
+#ifndef _PORTABLE_SOURCE
 #include <slibc/version.h>
 
 
@@ -48,4 +49,5 @@ void* alloca(size_t size);
 
 
 #endif
+#endif
 
diff --git a/include/assert.h b/include/assert.h
index 763b7b4..12d4678 100644
--- a/include/assert.h
+++ b/include/assert.h
@@ -58,6 +58,7 @@
 #define static_assert _Static_assert
 
 
+#ifndef _PORTABLE_SOURCE
 /**
  * Unless `NDEBUG` is defined, print an error message
  * and abort the process, if `errnum` is non-zero.
@@ -90,6 +91,7 @@
  */
 void __assert_fail(const char* expression, int errnum, const char* file, int line, const char* func)
   __noreturn __GCC_ONLY(__attribute__((nonnull(3, 4, 5))));
+#endif
 
 
 
diff --git a/include/err.h b/include/err.h
index 9eb01f3..2599feb 100644
--- a/include/err.h
+++ b/include/err.h
@@ -17,6 +17,7 @@
  */
 #ifndef _ERR_H
 #define _ERR_H
+#fifndef _PORTABLE_SOURCE
 #include <slibc/version.h>
 
 #ifndef _SLIBC_SUPPRESS_WARNINGS
@@ -116,4 +117,5 @@ void verrx(int status, const char* format, va_list args)
 
 
 #endif
+#endif
 
diff --git a/include/errno.h b/include/errno.h
index 0b6232f..0415cfb 100644
--- a/include/errno.h
+++ b/include/errno.h
@@ -41,6 +41,7 @@
 volatile int* __errno(void) __GCC_ONLY(__attribute__((__const__))); /* TODO not implemented */
 
 
+#ifndef _PORTABLE_SOURCE
 /**
  * This is the name that was used to invoke the program
  * running in the current process. This is the value
@@ -74,6 +75,7 @@ extern char* program_invocation_name; /* TODO not implemented */
 #if defined(_GNU_SOURCE)
 extern char* program_invocation_short_name; /* TODO not implemented */
 #endif
+#endif