Move bionic over to GCC's 'warning' attribute.
This is a better solution than the old __warn_references because it's
a compile-time rather than link-time warning, it doesn't rely on something
that doesn't appear to be supported by gold (which is why you only used
to see these warnings on mips builds), and the errors refer to the exact
call site(s) rather than just telling you which object file contains a
reference to the bad function.
This is primarily so we can build bionic for aarch64; building libc.so
caused these warnings to fire (because link time is the wrong time) and
warnings are errors.
Change-Id: I5df9281b2a9d98b164a9b11807ea9472c6faa9e3
diff --git a/libc/include/stdio.h b/libc/include/stdio.h
index 409afea..260a4e7 100644
--- a/libc/include/stdio.h
+++ b/libc/include/stdio.h
@@ -222,13 +222,13 @@
ssize_t getdelim(char ** __restrict, size_t * __restrict, int,
FILE * __restrict);
ssize_t getline(char ** __restrict, size_t * __restrict, FILE * __restrict);
-char *gets(char *);
+
#if __BSD_VISIBLE && !defined(__SYS_ERRLIST)
#define __SYS_ERRLIST
-
extern int sys_nerr; /* perror(3) external variables */
extern char *sys_errlist[];
#endif
+
void perror(const char *);
int printf(const char * __restrict, ...)
__printflike(1, 2);
@@ -251,13 +251,16 @@
__printflike(1, 0);
#ifndef __AUDIT__
-char *gets(char *);
-int sprintf(char * __restrict, const char * __restrict, ...)
- __printflike(2, 3);
-char *tmpnam(char *);
-int vsprintf(char * __restrict, const char * __restrict,
- __va_list)
- __printflike(2, 0);
+char* gets(char*) __warnattr("gets is very unsafe; consider using fgets");
+int sprintf(char* __restrict, const char* __restrict, ...)
+ __printflike(2, 3) __warnattr("sprintf is often misused; please use snprintf");
+char* tmpnam(char*) __warnattr("tmpnam possibly used unsafely; consider using mkstemp");
+int vsprintf(char* __restrict, const char* __restrict, __va_list)
+ __printflike(2, 0) __warnattr("vsprintf is often misused; please use vsnprintf");
+#if __XPG_VISIBLE
+char* tempnam(const char*, const char*)
+ __warnattr("tempnam possibly used unsafely; consider using mkstemp");
+#endif
#endif
extern int rename(const char*, const char*);
@@ -320,9 +323,6 @@
int putchar_unlocked(int);
#endif /* __POSIX_VISIBLE >= 199506 */
-#if __XPG_VISIBLE
-char *tempnam(const char *, const char *);
-#endif
__END_DECLS
#endif /* __BSD_VISIBLE || __POSIX_VISIBLE || __XPG_VISIBLE */
diff --git a/libc/include/stdlib.h b/libc/include/stdlib.h
index 9fa84c1..72b554f 100644
--- a/libc/include/stdlib.h
+++ b/libc/include/stdlib.h
@@ -51,9 +51,9 @@
extern int unsetenv(const char *);
extern int clearenv(void);
-extern char *mkdtemp(char *);
-extern char *mktemp(char *);
-extern int mkstemp(char *);
+extern char* mkdtemp(char*);
+extern char* mktemp(char*) __warnattr("mktemp possibly used unsafely; consider using mkstemp");
+extern int mkstemp(char*);
extern long strtol(const char *, char **, int);
extern long long strtoll(const char *, char **, int);
diff --git a/libc/include/sys/cdefs.h b/libc/include/sys/cdefs.h
index c7f2ac7..b4dad74 100644
--- a/libc/include/sys/cdefs.h
+++ b/libc/include/sys/cdefs.h
@@ -334,8 +334,10 @@
#if __GNUC_PREREQ__(4, 3)
#define __errordecl(name, msg) extern void name(void) __attribute__((__error__(msg)))
+#define __warnattr(msg) __attribute__((__warning__(msg)))
#else
#define __errordecl(name, msg) extern void name(void)
+#define __warnattr(msg)
#endif
/*
diff --git a/libc/include/sys/cdefs_elf.h b/libc/include/sys/cdefs_elf.h
index 0887fa5..bb846b7 100644
--- a/libc/include/sys/cdefs_elf.h
+++ b/libc/include/sys/cdefs_elf.h
@@ -38,20 +38,10 @@
#define _C_LABEL_STRING(x) x
#endif
-#if __STDC__
#define ___RENAME(x) __asm__(___STRING(_C_LABEL(x)))
-#else
-#ifdef __LEADING_UNDERSCORE
-#define ___RENAME(x) ____RENAME(_/**/x)
-#define ____RENAME(x) __asm__(___STRING(x))
-#else
-#define ___RENAME(x) __asm__(___STRING(x))
-#endif
-#endif
#define __indr_reference(sym,alias) /* nada, since we do weak refs */
-#if __STDC__
#define __strong_alias(alias,sym) \
__asm__(".global " _C_LABEL_STRING(#alias) "\n" \
_C_LABEL_STRING(#alias) " = " _C_LABEL_STRING(#sym));
@@ -61,39 +51,15 @@
_C_LABEL_STRING(#alias) " = " _C_LABEL_STRING(#sym));
#define __weak_extern(sym) \
__asm__(".weak " _C_LABEL_STRING(#sym));
+
+/* We use __warnattr instead of __warn_references.
+ * TODO: remove this and put an empty definition in one of the upstream-* compatibility headers.
+ */
#define __warn_references(sym,msg) \
- __asm__(".section .gnu.warning." #sym "\n\t.ascii \"" msg "\"\n\t.text");
+ /*__asm__(".section .gnu.warning." #sym "\n\t.ascii \"" msg "\"\n\t.text");*/
-#else /* !__STDC__ */
-
-#ifdef __LEADING_UNDERSCORE
-#define __weak_alias(alias,sym) ___weak_alias(_/**/alias,_/**/sym)
-#define ___weak_alias(alias,sym) \
- __asm__(".weak alias\nalias = sym");
-#else
-#define __weak_alias(alias,sym) \
- __asm__(".weak alias\nalias = sym");
-#endif
-#ifdef __LEADING_UNDERSCORE
-#define __weak_extern(sym) ___weak_extern(_/**/sym)
-#define ___weak_extern(sym) \
- __asm__(".weak sym");
-#else
-#define __weak_extern(sym) \
- __asm__(".weak sym");
-#endif
-#define __warn_references(sym,msg) \
- __asm__(".section .gnu.warning.sym\n\t.ascii msg ; .text");
-
-#endif /* !__STDC__ */
-
-#if __STDC__
#define __SECTIONSTRING(_sec, _str) \
__asm__(".section " #_sec "\n\t.asciz \"" _str "\"\n\t.previous")
-#else
-#define __SECTIONSTRING(_sec, _str) \
- __asm__(".section _sec\n\t.asciz _str\n\t.previous")
-#endif
/* GCC visibility helper macro */
/* This must be used to tag non-static functions that are private, i.e.