| Summary: | [12 Regression] Missing memmem() prototype in fixincludes/fixfixes.c on Windows/MinGW-W64 | ||
|---|---|---|---|
| Product: | gcc | Reporter: | Jan Dubiec <jdx> |
| Component: | other | Assignee: | Xi Ruoyao <xry111> |
| Status: | RESOLVED FIXED | ||
| Severity: | normal | CC: | sjames, xry111 |
| Priority: | P3 | Keywords: | build, patch |
| Version: | 13.0 | ||
| Target Milestone: | 12.3 | ||
| URL: | https://gcc.gnu.org/pipermail/gcc-patches/2023-March/614709.html | ||
| See Also: | https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91085 | ||
| Host: | x86_64-w64-mingw32 | Target: | |
| Build: | Known to work: | ||
| Known to fail: | Last reconfirmed: | 2023-03-27 00:00:00 | |
| Attachments: | Proposed patch | ||
Started with r12-1924-g6bf383c37e6131 . I'll make a patch to check if memmem is declared in configure.ac. memmem is not a POSIX function, so it may be undeclared on systems other than MinGW as well. (In reply to Xi Ruoyao from comment #2) > I'll make a patch to check if memmem is declared in configure.ac. memmem is > not a POSIX function, so it may be undeclared on systems other than MinGW as > well. memmem is included in libiberty so it is more just about the prototype not being declared. (In reply to Andrew Pinski from comment #3) > (In reply to Xi Ruoyao from comment #2) > > I'll make a patch to check if memmem is declared in configure.ac. memmem is > > not a POSIX function, so it may be undeclared on systems other than MinGW as > > well. > > memmem is included in libiberty so it is more just about the prototype not > being declared. libiberty configure.ac checked it with AC_CHECK_FUNCS, so if the system libc does not provide memmem, libiberty will build its copy. And we just need to declare the prototype to use it, as libiberty doc says: https://gcc.gnu.org/onlinedocs/libiberty/Supplemental-Functions.html Something like this: diff --git a/fixincludes/configure.ac b/fixincludes/configure.ac index 14813b910f1..00aeb1ce1d9 100644 --- a/fixincludes/configure.ac +++ b/fixincludes/configure.ac @@ -89,6 +89,7 @@ define(fixincludes_UNLOCKED_FUNCS, clearerr_unlocked feof_unlocked dnl putchar_unlocked putc_unlocked) AC_CHECK_FUNCS(fixincludes_UNLOCKED_FUNCS) AC_CHECK_DECLS([abort, asprintf, basename(char *), errno, vasprintf]) +AC_CHECK_DECLS([memmem]) AC_CHECK_DECLS(m4_split(m4_normalize(fixincludes_UNLOCKED_FUNCS))) # Checks for typedefs, structures, and compiler characteristics. diff --git a/fixincludes/system.h b/fixincludes/system.h index dca5d57b2e3..f7bbd0e952c 100644 --- a/fixincludes/system.h +++ b/fixincludes/system.h @@ -209,6 +209,11 @@ extern int errno; extern void abort (void); #endif +#if defined (HAVE_DECL_MEMMEM) && !HAVE_DECL_MEMMEM +extern void *memmem (const void *, size_t, const void *, size_t); +#endif + + #if HAVE_SYS_STAT_H # include <sys/stat.h> #endif (In reply to Andrew Pinski from comment #5) > Something like this: > diff --git a/fixincludes/configure.ac b/fixincludes/configure.ac > index 14813b910f1..00aeb1ce1d9 100644 > --- a/fixincludes/configure.ac > +++ b/fixincludes/configure.ac > @@ -89,6 +89,7 @@ define(fixincludes_UNLOCKED_FUNCS, clearerr_unlocked > feof_unlocked dnl > putchar_unlocked putc_unlocked) > AC_CHECK_FUNCS(fixincludes_UNLOCKED_FUNCS) > AC_CHECK_DECLS([abort, asprintf, basename(char *), errno, vasprintf]) > +AC_CHECK_DECLS([memmem]) > AC_CHECK_DECLS(m4_split(m4_normalize(fixincludes_UNLOCKED_FUNCS))) > > # Checks for typedefs, structures, and compiler characteristics. > diff --git a/fixincludes/system.h b/fixincludes/system.h > index dca5d57b2e3..f7bbd0e952c 100644 > --- a/fixincludes/system.h > +++ b/fixincludes/system.h > @@ -209,6 +209,11 @@ extern int errno; > extern void abort (void); > #endif > > +#if defined (HAVE_DECL_MEMMEM) && !HAVE_DECL_MEMMEM > +extern void *memmem (const void *, size_t, const void *, size_t); > +#endif > + > + > #if HAVE_SYS_STAT_H > # include <sys/stat.h> > #endif Yes, I'm testing it in a container environment where I've removed memmem from system string.h. The master branch has been updated by Xi Ruoyao <xry111@gcc.gnu.org>: https://gcc.gnu.org/g:21c74b6ea41d21ef96813b34bfa55c51a82d6c99 commit r13-6888-g21c74b6ea41d21ef96813b34bfa55c51a82d6c99 Author: Xi Ruoyao <xry111@xry111.site> Date: Tue Mar 28 01:48:02 2023 +0800 fixincludes: Declare memmem if it's not declared in system headers [PR109293] memmem is not POSIX so the system may lack it. Then libiberty will provide an implementation, but it's a "supplemental function" and not declared in libiberty.h. We need to declare the prototype to use it then. See libiberty doc at https://gcc.gnu.org/onlinedocs/libiberty/Supplemental-Functions.html. Tested by bootstrapping GCC in the following container environments on x86_64-linux-gnu: 1. "Vanilla" system with memmem in Glibc. 2. memmem removed from string.h. 3. memmem removed from both string.h and libc.so. For 3, also verified that memmem from libiberty is linked into fixincl executable. Ok for trunk? fixincludes/ChangeLog: PR other/109293 * configure.ac (AC_CHECK_DECLS): Add memmem. * configure: Regenerate. * config.h.in: Regenerate. * system.h (memmem): Declare if HAVE_DECL_MEMMEM is zero. Will backport the fix into gcc-12 after a bootstrap as verification. I can confirm that now everything is fine on this issue on Windows/MingW. The releases/gcc-12 branch has been updated by Xi Ruoyao <xry111@gcc.gnu.org>: https://gcc.gnu.org/g:743088c3c7c670f180978dd7b59a57fd9626c5a2 commit r12-9326-g743088c3c7c670f180978dd7b59a57fd9626c5a2 Author: Xi Ruoyao <xry111@xry111.site> Date: Tue Mar 28 01:48:02 2023 +0800 fixincludes: Declare memmem if it's not declared in system headers [PR109293] memmem is not POSIX so the system may lack it. Then libiberty will provide an implementation, but it's a "supplemental function" and not declared in libiberty.h. We need to declare the prototype to use it then. See libiberty doc at https://gcc.gnu.org/onlinedocs/libiberty/Supplemental-Functions.html. Tested by bootstrapping GCC in the following container environments on x86_64-linux-gnu: 1. "Vanilla" system with memmem in Glibc. 2. memmem removed from string.h. 3. memmem removed from both string.h and libc.so. For 3, also verified that memmem from libiberty is linked into fixincl executable. Note that the backport does not contain a complete regeneration of configure and config.h.in (attempting such regeneration resulted in all the USED_FOR_TARGET conditional disappearing; this already happened in trunk at r13-2200). fixincludes/ChangeLog: PR other/109293 * configure.ac (AC_CHECK_DECLS): Add memmem. * configure: Regenerate. * config.h.in: Regenerate. * system.h (memmem): Declare if HAVE_DECL_MEMMEM is zero. (cherry picked from commit 21c74b6ea41d21ef96813b34bfa55c51a82d6c99) Fixed for trunk and gcc-12. |
Created attachment 54763 [details] Proposed patch gcc -c -g -O2 -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition -Wmissing-format-attribute -Wno-overlength-strings -pedantic -Wno-long-long -DHAVE_CONFIG_H -I. -I../../../gcc/fixincludes -I../include -I../../../gcc/fixincludes/../include ../../../gcc/fixincludes/fixfixes.c ../../../gcc/fixincludes/fixfixes.c: In function 'check_has_inc': ../../../gcc/fixincludes/fixfixes.c:490:12: warning: implicit declaration of function 'memmem'; did you mean 'memset'? [-Wimplicit-function-declaration] 490 | for (p = memmem (begin, pos - begin, has_inc, has_inc_len); | ^~~~~~ | memset ../../../gcc/fixincludes/fixfixes.c:490:10: warning: assignment to 'const char *' from 'int' makes pointer from integer without a cast [-Wint-conversion] 490 | for (p = memmem (begin, pos - begin, has_inc, has_inc_len); | ^ ../../../gcc/fixincludes/fixfixes.c:492:10: warning: assignment to 'const char *' from 'int' makes pointer from integer without a cast [-Wint-conversion] 492 | p = memmem (p, pos - p, has_inc, has_inc_len)) | ^