Squash a ton of warnings, including with gcc

zerocc2014 · May 31, 2020 · 6ae0170 · 6ae0170
1 parent fcb0599
commit 6ae0170
Show file tree

Hide file tree

Showing 15 changed files with 71 additions and 33 deletions.
diff --git a/emu/cpu.h b/emu/cpu.h
@@ -219,8 +219,8 @@ static inline const char *reg32_name(enum reg32 reg) {
         case reg_ebp: return "ebp";
         case reg_esi: return "esi";
         case reg_edi: return "edi";
-        case reg_none: return "?";
     }
+    return "?";
 }
 
 #endif
diff --git a/emu/decode.h b/emu/decode.h
@@ -246,6 +246,7 @@ __no_instrument DECODER_RET glue(DECODER_NAME, OP_SIZE)(DECODER_ARGS) {
                                        CMPXCHG8B(modrm_val,64); break;
                                default: UNDEFINED;
                            };
+                           break;
 
 #if OP_SIZE != 16
                 case 0xc8: TRACEI("bswap eax");

diff --git a/emu/float80.c b/emu/float80.c
@@ -34,7 +34,7 @@ static int unbias_denormal(unsigned exp) {
 
 __thread enum f80_rounding_mode f80_rounding_mode;
 
-static bool round_away_from_zero(sign) {
+static bool round_away_from_zero(int sign) {
     return (f80_rounding_mode == round_up && !sign) ||
         (f80_rounding_mode == round_down && sign);
 }

diff --git a/emu/fpu.h b/emu/fpu.h
@@ -17,7 +17,7 @@ enum fpu_const {
     fconst_ln2 = 5,
     fconst_zero = 6,
 };
-static float80 fpu_consts[] = {
+static const float80 fpu_consts[] = {
     [fconst_one]   = (float80) {.signif = 0x8000000000000000, .signExp = 0x3fff},
     [fconst_log2t] = (float80) {.signif = 0xd49a784bcd1b8afe, .signExp = 0x4000},
     [fconst_log2e] = (float80) {.signif = 0xb8aa3b295c17f0bc, .signExp = 0x3fff},

diff --git a/emu/modrm.h b/emu/modrm.h
@@ -12,14 +12,14 @@
 struct modrm {
     union {
         enum reg32 reg;
-        int opcode;
+        unsigned opcode;
     };
     enum {
         modrm_reg, modrm_mem, modrm_mem_si
     } type;
     union {
         enum reg32 base;
-        int rm_opcode;
+        unsigned rm_opcode;
     };
     int32_t offset;
     enum reg32 index;
@@ -30,11 +30,9 @@ struct modrm {
     } shift;
 };
 
-enum {
-    rm_sib = reg_esp,
-    rm_none = reg_esp,
-    rm_disp32 = reg_ebp,
-};
+static const unsigned rm_sib = reg_esp;
+static const unsigned rm_none = reg_esp;
+static const unsigned rm_disp32 = reg_ebp;
 #define MOD(byte) ((byte & 0b11000000) >> 6)
 #define REG(byte) ((byte & 0b00111000) >> 3)
 #define RM(byte)  ((byte & 0b00000111) >> 0)

diff --git a/fs/sock.c b/fs/sock.c
@@ -1161,7 +1161,13 @@ const struct fd_ops socket_fdops = {
     .ioctl = realfs_ioctl,
 };
 
+#if defined(__GNUC__)
+#if defined(__clang__)
 #pragma GCC diagnostic ignored "-Wmissing-field-initializers"
+#else
+#pragma GCC diagnostic ignored "-Wcast-function-type"
+#endif
+#endif
 static struct socket_call {
     syscall_t func;
     int args;

diff --git a/fs/tty-real.c b/fs/tty-real.c
@@ -15,7 +15,8 @@
 
 void real_tty_reset_term(void);
 
-static void real_tty_read_thread(struct tty *tty) {
+static void *real_tty_read_thread(void *_tty) {
+    struct tty *tty = _tty;
     char ch;
     for (;;) {
         int err = read(STDIN_FILENO, &ch, 1);
@@ -32,6 +33,7 @@ static void real_tty_read_thread(struct tty *tty) {
         }
         tty_input(tty, &ch, 1, 0);
     }
+    return NULL;
 }
 
 static struct termios_ termios_from_real(struct termios real) {
@@ -109,7 +111,7 @@ static int real_tty_init(struct tty *tty) {
         ERRNO_DIE("failed to set terminal to raw mode");
 notty:
 
-    if (pthread_create(&tty->thread, NULL, (void *(*)(void *)) real_tty_read_thread, tty) < 0)
+    if (pthread_create(&tty->thread, NULL,  real_tty_read_thread, tty) < 0)
         // ok if this actually happened it would be weird AF
         return _EIO;
     pthread_detach(tty->thread);

diff --git a/fs/tty.c b/fs/tty.c
@@ -667,6 +667,7 @@ static int tty_mode_ioctl(struct tty *in_tty, int cmd, void *arg) {
         case TCSETSF_:
             tty->bufsize = 0;
             notify(&tty->consumed);
+            fallthrough;
         case TCSETSW_:
             // we have no output buffer currently
         case TCSETS_:
@@ -704,7 +705,7 @@ static int tty_ioctl(struct fd *fd, int cmd, void *arg) {
     switch (cmd) {
         case TCFLSH_:
             // only input flushing is currently useful
-            switch ((dword_t) arg) {
+            switch ((uintptr_t) arg) {
                 case TCIFLUSH_:
                 case TCIOFLUSH_:
                     tty->bufsize = 0;
@@ -719,7 +720,7 @@ static int tty_ioctl(struct fd *fd, int cmd, void *arg) {
             break;
 
         case TIOCSCTTY_:
-            err = tiocsctty(tty, (dword_t) arg);
+            err = tiocsctty(tty, (uintptr_t) arg);
             break;
 
         case TIOCGPRGP_:

diff --git a/kernel/calls.c b/kernel/calls.c
@@ -9,6 +9,9 @@ dword_t syscall_success_stub() {
     return 0;
 }
 
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic ignored "-Wcast-function-type"
+#endif
 syscall_t syscall_table[] = {
     [1]   = (syscall_t) sys_exit,
     [2]   = (syscall_t) sys_fork,

diff --git a/kernel/log.c b/kernel/log.c
@@ -61,7 +61,7 @@ static int do_syslog(int type, addr_t buf_addr, int_t len) {
             res = syslog_read(buf_addr, len, FIFO_LAST | FIFO_PEEK);
             if (res < 0)
                 return res;
-            // fallthrough
+            fallthrough;
         case SYSLOG_ACTION_CLEAR_:
             log_max_since_clear = 0;
             return 0;

diff --git a/kernel/signal.c b/kernel/signal.c
@@ -7,6 +7,10 @@
 #include "kernel/vdso.h"
 #include "emu/interrupt.h"
 
+#if defined(__GNUC__) && !defined(__clang__)
+#pragma GCC diagnostic ignored "-Waddress-of-packed-member"
+#endif
+
 int xsave_extra = 0;
 int fxsave_extra = 0;
 static void sigmask_set(sigset_t_ set);
@@ -285,9 +289,10 @@ static void receive_signal(struct sighand *sighand, struct siginfo_ *info) {
     }
 
     // install frame
-    (void) user_write(sp, &frame, frame_size);
-    // nothing we can do if that fails
-    // TODO do something other than nothing, like printk maybe
+    if (user_write(sp, &frame, frame_size)) {
+        printk("failed to install frame for %d at %#x\n", info->sig, sp);
+        deliver_signal(current, SIGSEGV_, SIGINFO_NIL);
+    }
 }
 
 void receive_signals() {
@@ -356,7 +361,10 @@ dword_t sys_rt_sigreturn() {
     struct cpu_state *cpu = &current->cpu;
     struct rt_sigframe_ frame;
     // esp points past the first field of the frame
-    (void) user_get(cpu->esp - offsetof(struct rt_sigframe_, sig), frame);
+    if (user_get(cpu->esp - offsetof(struct rt_sigframe_, sig), frame)) {
+        deliver_signal(current, SIGSEGV_, SIGINFO_NIL);
+        return _EFAULT;
+    }
     restore_sigcontext(&frame.uc.mcontext, cpu);
 
     lock(&current->sighand->lock);
@@ -375,8 +383,10 @@ dword_t sys_sigreturn() {
     struct cpu_state *cpu = &current->cpu;
     struct sigframe_ frame;
     // esp points past the first two fields of the frame
-    (void) user_get(cpu->esp - offsetof(struct sigframe_, sc), frame);
-    // TODO check for errors in that
+    if (user_get(cpu->esp - offsetof(struct sigframe_, sc), frame)) {
+        deliver_signal(current, SIGSEGV_, SIGINFO_NIL);
+        return _EFAULT;
+    }
     restore_sigcontext(&frame.sc, cpu);
 
     lock(&current->sighand->lock);

diff --git a/meson.build b/meson.build
@@ -1,6 +1,10 @@
 project('ish', 'c',
     default_options: ['default_library=static', 'c_std=gnu11', 'warning_level=2'])
 
+if meson.get_compiler('c').get_id() == 'clang'
+    add_project_arguments('-Wimplicit-fallthrough', '-Wtautological-constant-in-range-compare', language: 'c')
+endif
+
 log_on = get_option('log').split()
 log_off = get_option('nolog').split()
 foreach channel : log_on + log_off

diff --git a/misc.h b/misc.h
@@ -30,8 +30,17 @@
 #define unlikely(x) __builtin_expect((x), 0)
 #define typecheck(type, x) ({type _x = x; x;})
 #define must_check __attribute__((warn_unused_result))
+#define fallthrough __attribute__((fallthrough))
+
 #if defined(__has_attribute) && __has_attribute(no_sanitize)
-#define __no_instrument __attribute__((no_sanitize("address", "thread", "undefined", "leak", "memory")))
+#define __no_instrument_msan
+#if defined(__has_feature)
+#if __has_feature(memory_sanitizer)
+#undef __no_instrument_msan
+#define __no_instrument_msan __attribute__((no_sanitize("memory"))
+#endif
+#endif
+#define __no_instrument __attribute__((no_sanitize("address", "thread", "undefined", "leak"))) __no_instrument_msan
 #else
 #define __no_instrument
 #endif

diff --git a/tools/ptraceomatic.c b/tools/ptraceomatic.c
@@ -233,12 +233,15 @@ static void remote_close_fd(int pid, int fd, long int80_ip) {
     setregs(pid, &regs);
 }
 
+#define _ignore(x) {}; int UNUSED(x) =
+#define ignore _ignore(__COUNTER__)
+
 static void pt_copy(int pid, addr_t start, size_t size) {
     if (start == 0)
         return;
     byte_t byte;
     for (addr_t addr = start; addr < start + size; addr++) {
-        (void) user_get(addr, byte);
+        ignore user_get(addr, byte);
         pt_write8(pid, addr, byte);
     }
 }
@@ -248,7 +251,7 @@ static void pt_copy_to_real(int pid, addr_t start, size_t size) {
     byte_t byte;
     for (addr_t addr = start; addr < start + size; addr++) {
         pt_readn(pid, addr, &byte, sizeof(byte));
-        (void) user_put(addr, byte);
+        ignore user_put(addr, byte);
     }
 }
 
@@ -321,19 +324,19 @@ static void step_tracing(struct cpu_state *cpu, struct tlb *tlb, int pid, int se
                 pt_copy(pid, regs.rcx, regs.rdx); break;
             case 102: { // socketcall
                 dword_t args[6];
-                (void) user_get(regs.rcx, args);
+                ignore user_get(regs.rcx, args);
                 dword_t len;
                 switch (cpu->ebx) {
                     case 6: // getsockname
-                        (void) user_get(args[2], len);
+                        ;ignore user_get(args[2], len);
                         pt_copy(pid, args[1], len);
                         break;
                     case 8: // socketpair
                         pt_copy(pid, args[3], sizeof(dword_t[2]));
                         break;
                     case 12: // recvfrom
                         pt_copy(pid, args[1], args[2]);
-                        (void) user_get(args[5], len);
+                        ignore user_get(args[5], len);
                         pt_copy(pid, args[4], len);
                         break;
                 }
@@ -349,7 +352,7 @@ static void step_tracing(struct cpu_state *cpu, struct tlb *tlb, int pid, int se
                 pt_copy(pid, regs.rsi, 8); break;
             case 145: { // readv
                 struct iovec_ vecs[regs.rdx];
-                (void) user_get(regs.rcx, vecs);
+                ignore user_get(regs.rcx, vecs);
                 for (unsigned i = 0; i < regs.rdx; i++)
                     pt_copy(pid, vecs[i].base, vecs[i].len);
                 break;
@@ -361,7 +364,8 @@ static void step_tracing(struct cpu_state *cpu, struct tlb *tlb, int pid, int se
             case 183: // getcwd
                 pt_copy(pid, regs.rbx, cpu->eax); break;
             case 186: // sigaltstack
-                if (regs.rcx != 0) pt_copy(pid, regs.rcx, sizeof(struct stack_t_)); break;
+                if (regs.rcx != 0) pt_copy(pid, regs.rcx, sizeof(struct stack_t_));
+                break;
             case 195: // stat64
             case 196: // lstat64
             case 197: // fstat64
@@ -375,9 +379,11 @@ static void step_tracing(struct cpu_state *cpu, struct tlb *tlb, int pid, int se
             case 300: // fstatat64
                 pt_copy(pid, regs.rdx, sizeof(struct newstat64)); break;
             case 305: // readlinkat
-                if (cpu->eax < 0xffff000) pt_copy(pid, regs.rdx, cpu->eax); break;
+                if (cpu->eax < 0xffff000) pt_copy(pid, regs.rdx, cpu->eax);
+                break;
             case 340: // prlimit
-                if (regs.rsi != 0) pt_copy(pid, regs.rsi, sizeof(struct rlimit_)); break;
+                if (regs.rsi != 0) pt_copy(pid, regs.rsi, sizeof(struct rlimit_));
+                break;
             case 355: // getrandom
                 pt_copy(pid, regs.rbx, regs.rcx); break;
 

diff --git a/xX_main_Xx.h b/xX_main_Xx.h
@@ -46,7 +46,6 @@ static inline int xX_main_Xx(int argc, char *const argv[], const char *envp) {
     // parse cli options
     int opt;
     const char *root = NULL;
-    bool has_root = false;
     const char *workdir = NULL;
     const struct fs_ops *fs = &realfs;
     const char *console = "/dev/tty1";
@@ -55,7 +54,6 @@ static inline int xX_main_Xx(int argc, char *const argv[], const char *envp) {
             case 'r':
             case 'f':
                 root = optarg;
-                has_root = true;
                 if (opt == 'f')
                     fs = &fakefs;
                 break;