https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103650
Bug ID: 103650
Summary: [9/10/11/12 Regression] libstdc++ headers defined
LT_OBJDIR and STDC_HEADERS
Product: gcc
Version: 11.2.1
Status: UNCONFIRMED
Keywords: rejects-valid
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: redi at gcc dot gnu.org
Target Milestone: ---
#define LT_OBJDIR 99
#define STDC_HEADERS 99
#include <utility>
#if LT_OBJDIR != 99
# error LT_OBJDIR redefined
#endif
#if STDC_HEADERS != 99
# error STDC_HEADERS redefined
#endif
In file included from /usr/include/c++/11/utility:68,
from macros.C:3:
macros.C:4:5: error: token "".libs/"" is not valid in preprocessor expressions
4 | #if LT_OBJDIR != 99
| ^~~~~~~~~
macros.C:8:3: error: #error STDC_HEADERS redefined
8 | # error STDC_HEADERS redefined
| ^~~~~
With GCC 4.1 only STDC_HEADERS was defined:
macros.C:8:3: error: #error STDC_HEADERS redefined
So the definition of LT_OBJDIR in 4.3 and later (I can't check 4.2) is a
regression.
We never asked for those macros, this is libtool and autoconf being "helpful".
