Added functionality to mark printf() functions for compilers with warning checks, and marked such. Sadly it appears ms_printf is ignored with -pedantic, so we'll need to stop using I32...

common/uipriv.h

@@ -28,9 +28,14 @@ extern "C" {
 #define uiprivSizetPrintf "zu"
 #endif
 
+#include "../sharedbits/printfwarn_header.h"
+#define uiprivPrintfFunc(decl, fmtpos, appos) sharedbitsPrintfFunc(decl, fmtpos, appos)
+
 // main.c
 extern bool uiprivSysInit(void *options, uiInitError *err);
-extern bool uiprivInitReturnErrorf(uiInitError *err, const char *fmt, ...);
+uiprivPrintfFunc(
+	extern bool uiprivInitReturnErrorf(uiInitError *err, const char *fmt, ...),
+	2, 3);
 extern void uiprivSysQueueMain(void (*f)(void *data), void *data);
 extern bool uiprivCheckInitializedAndThreadImpl(const char *func);
 #define uiprivCheckInitializedAndThread() uiprivCheckInitializedAndThreadImpl(uiprivFunc)
@@ -49,7 +54,9 @@ extern bool uiprivSysCheckThread(void);
 #undef sharedbitsPrefix
 
 // errors.c
-extern void uiprivInternalError(const char *fmt, ...);
+uiprivPrintfFunc(
+	extern void uiprivInternalError(const char *fmt, ...),
+	1, 2);
 enum {
 	uiprivProgrammerErrorNotInitialized,		// arguments: uiprivFunc
 	uiprivProgrammerErrorWrongThread,		// arguments: uiprivFunc
@@ -63,6 +70,7 @@ enum {
 	uiprivProgrammerErrorRecursiveEventFire,	// no arguments
 	uiprivNumProgrammerErrors,
 };
+// TODO drop the enum and make the above all format strings
 extern void uiprivProgrammerError(unsigned int which, ...);
 extern void uiprivReportError(const char *prefix, const char *msg, const char *suffix, bool internal);
 

sharedbits/alloc_impl.h

@@ -3,7 +3,10 @@
 
 #include "start.h"
 
-extern void sharedbitsPrefixName(InternalError)(const char *fmt, ...);
+#include "printfwarn_header.h"
+sharedbitsPrintfFunc(
+	extern void sharedbitsPrefixName(InternalError)(const char *fmt, ...),
+	1, 2);
 
 void *sharedbitsPrefixName(Alloc)(size_t n, const char *what)
 {

sharedbits/printfwarn_header.h

@@ -0,0 +1,14 @@
+// 1 june 2019
+
+#ifdef __GNUC__
+#ifdef _WIN32
+#define sharedbitsPrintfFunc(decl, fmtpos, appos) \
+	decl __attribute__((format(ms_printf, fmtpos, appos)))
+#else
+#define sharedbitsPrintfFunc(decl, fmtpos, appos) \
+	decl __attribute__((format(printf, fmtpos, appos)))
+#endif
+#else
+#define sharedbitsPrintfFunc(decl, fmtpos, appos) \
+	decl
+#endif

sharedbits/strsafe_strncpy_impl.h

@@ -8,12 +8,15 @@
 #define sharedbitsprivInternalError sharedbitsInternalError
 #else
 #define sharedbitsprivInternalError sharedbitsPrefixName(InternalError)
+#include "printfwarn_header.h"
 #ifdef sharedbitsStatic
 sharedbitsStatic
 #else
 extern
 #endif
-void sharedbitsprivInternalError(const char *fmt, ...);
+sharedbitsPrintfFunc(
+	void sharedbitsprivInternalError(const char *fmt, ...),
+	1, 2);
 #endif
 #endif
 

test/lib/testing.h

@@ -76,5 +76,9 @@ extern void testingprivSetRegisterTest(testingSet **pset, const char *, void (*)
 #define testingprivExpand(x) x
 #define testingprivTLogfThen(then, t, ...) ((testingprivTLogfFull(t, __FILE__, __LINE__, __VA_ARGS__)), (then(t)))
 #define testingprivTLogvfThen(then, t, format, ap) ((testingprivTLogvfFull(t, __FILE__, __LINE__, format, ap)), (then(t)))
-extern void testingprivTLogfFull(testingT *, const char *, long, const char *, ...);
+#include "../../sharedbits/printfwarn_header.h"
+sharedbitsPrintfFunc(
+	extern void testingprivTLogfFull(testingT *, const char *, long, const char *, ...),
+	4, 5);
+#undef sharedbitsPrintfFunc
 extern void testingprivTLogvfFull(testingT *, const char *, long, const char *, va_list);

test/lib/testingpriv.h

@@ -1,6 +1,10 @@
 // 19 may 2019
 
-extern void testingprivInternalError(const char *fmt, ...);
+#include "../../sharedbits/printfwarn_header.h"
+
+sharedbitsPrintfFunc(
+	extern void testingprivInternalError(const char *fmt, ...),
+	1, 2);
 
 #define sharedbitsPrefix testingpriv
 
@@ -18,10 +22,14 @@ extern void testingprivInternalError(const char *fmt, ...);
 #undef sharedbitsPrefix
 
 extern int testingprivVsnprintf(char *s, size_t n, const char *fmt, va_list ap);
-extern int testingprivSnprintf(char *s, size_t n, const char *fmt, ...);
+sharedbitsPrintfFunc(
+	extern int testingprivSnprintf(char *s, size_t n, const char *fmt, ...),
+	3, 4);
 extern char *testingprivStrdup(const char *s);
 extern char *testingprivVsmprintf(const char *fmt, va_list ap);
-extern char *testingprivSmprintf(const char *fmt, ...);
+sharedbitsPrintfFunc(
+	extern char *testingprivSmprintf(const char *fmt, ...),
+	1, 2);
 
 // a testingprivOutbuf of NULL writes directly to stdout
 typedef struct testingprivOutbuf testingprivOutbuf;
@@ -29,6 +37,10 @@ extern testingprivOutbuf *testingprivNewOutbuf(void);
 extern void testingprivOutbufFree(testingprivOutbuf *o);
 extern void testingprivOutbufVprintf(testingprivOutbuf *o, const char *fmt, va_list ap);
 extern void testingprivOutbufVprintfIndented(testingprivOutbuf *o, const char *fmt, va_list ap);
-extern void testingprivOutbufPrintf(testingprivOutbuf *o, const char *fmt, ...);
+sharedbitsPrintfFunc(
+	extern void testingprivOutbufPrintf(testingprivOutbuf *o, const char *fmt, ...),
+	2, 3);
 extern void testingprivOutbufAppendOutbuf(testingprivOutbuf *o, testingprivOutbuf *src);
 extern const char *testingprivOutbufString(testingprivOutbuf *o);
+
+#undef sharedbitsPrintfFunc